diff --git a/benchmark/_cli.js b/benchmark/_cli.js
index 45e4c7a2bf05fb..fa2bfb83955e73 100644
--- a/benchmark/_cli.js
+++ b/benchmark/_cli.js
@@ -65,7 +65,7 @@ function CLI(usage, settings) {
       // item arguments
       this.items.push(arg);
 
-      // the next value must be an item
+      // The next value must be an item
       mode = 'item';
     } else {
       // Bad case, abort
diff --git a/benchmark/net/net-c2s-cork.js b/benchmark/net/net-c2s-cork.js
index 38a0b17512e139..34c4b50296ec75 100644
--- a/benchmark/net/net-c2s-cork.js
+++ b/benchmark/net/net-c2s-cork.js
@@ -1,4 +1,4 @@
-// test the speed of .pipe() with sockets
+// Test the speed of .pipe() with sockets
 'use strict';
 
 const common = require('../common.js');
@@ -78,7 +78,7 @@ Writer.prototype.write = function(chunk, encoding, cb) {
   return true;
 };
 
-// doesn't matter, never emits anything.
+// Doesn't matter, never emits anything.
 Writer.prototype.on = function() {};
 Writer.prototype.once = function() {};
 Writer.prototype.emit = function() {};
diff --git a/benchmark/net/net-c2s.js b/benchmark/net/net-c2s.js
index 2d6ac85f5d25b0..732bda131d6b5a 100644
--- a/benchmark/net/net-c2s.js
+++ b/benchmark/net/net-c2s.js
@@ -1,4 +1,4 @@
-// test the speed of .pipe() with sockets
+// Test the speed of .pipe() with sockets
 'use strict';
 
 const common = require('../common.js');
@@ -72,7 +72,7 @@ Writer.prototype.write = function(chunk, encoding, cb) {
   return true;
 };
 
-// doesn't matter, never emits anything.
+// Doesn't matter, never emits anything.
 Writer.prototype.on = function() {};
 Writer.prototype.once = function() {};
 Writer.prototype.emit = function() {};
diff --git a/benchmark/net/net-pipe.js b/benchmark/net/net-pipe.js
index dc0b996dc389c5..12db1e13b836d2 100644
--- a/benchmark/net/net-pipe.js
+++ b/benchmark/net/net-pipe.js
@@ -1,4 +1,4 @@
-// test the speed of .pipe() with sockets
+// Test the speed of .pipe() with sockets
 'use strict';
 
 const common = require('../common.js');
@@ -75,7 +75,7 @@ Writer.prototype.write = function(chunk, encoding, cb) {
   return true;
 };
 
-// doesn't matter, never emits anything.
+// Doesn't matter, never emits anything.
 Writer.prototype.on = function() {};
 Writer.prototype.once = function() {};
 Writer.prototype.emit = function() {};
diff --git a/benchmark/net/net-s2c.js b/benchmark/net/net-s2c.js
index bb0a3121b9e9e3..848168cda45d83 100644
--- a/benchmark/net/net-s2c.js
+++ b/benchmark/net/net-s2c.js
@@ -1,4 +1,4 @@
-// test the speed of .pipe() with sockets
+// Test the speed of .pipe() with sockets
 'use strict';
 
 const common = require('../common.js');
@@ -73,7 +73,7 @@ Writer.prototype.write = function(chunk, encoding, cb) {
   return true;
 };
 
-// doesn't matter, never emits anything.
+// Doesn't matter, never emits anything.
 Writer.prototype.on = function() {};
 Writer.prototype.once = function() {};
 Writer.prototype.emit = function() {};
diff --git a/benchmark/net/net-wrap-js-stream-passthrough.js b/benchmark/net/net-wrap-js-stream-passthrough.js
index abea4b573d320e..1c597b6ed0a199 100644
--- a/benchmark/net/net-wrap-js-stream-passthrough.js
+++ b/benchmark/net/net-wrap-js-stream-passthrough.js
@@ -68,7 +68,7 @@ Writer.prototype.write = function(chunk, encoding, cb) {
   return true;
 };
 
-// doesn't matter, never emits anything.
+// Doesn't matter, never emits anything.
 Writer.prototype.on = function() {};
 Writer.prototype.once = function() {};
 Writer.prototype.emit = function() {};
diff --git a/benchmark/net/tcp-raw-s2c.js b/benchmark/net/tcp-raw-s2c.js
index 73f4d292cf5541..cc2f69019fff61 100644
--- a/benchmark/net/tcp-raw-s2c.js
+++ b/benchmark/net/tcp-raw-s2c.js
@@ -5,9 +5,9 @@
 const common = require('../common.js');
 const util = require('util');
 
-// if there are dur=N and len=N args, then
+// If there are dur=N and len=N args, then
 // run the function with those settings.
-// if not, then queue up a bunch of child processes.
+// If not, then queue up a bunch of child processes.
 const bench = common.createBenchmark(main, {
   len: [102400, 1024 * 1024 * 16],
   type: ['utf', 'asc', 'buf'],
diff --git a/benchmark/run.js b/benchmark/run.js
index 7af2245ef321c9..2eb1ab1a4b0905 100644
--- a/benchmark/run.js
+++ b/benchmark/run.js
@@ -50,7 +50,7 @@ if (format === 'csv') {
     for (const key of Object.keys(data.conf)) {
       conf += ` ${key}=${JSON.stringify(data.conf[key])}`;
     }
-    // delete first space of the configuration
+    // Delete first space of the configuration
     conf = conf.slice(1);
     if (format === 'csv') {
       // Escape quotes (") for correct csv formatting
diff --git a/benchmark/timers/immediate.js b/benchmark/timers/immediate.js
index 6a34becb918f48..ba50f961daa6aa 100644
--- a/benchmark/timers/immediate.js
+++ b/benchmark/timers/immediate.js
@@ -57,7 +57,7 @@ function depth1(N) {
   }
 }
 
-// concurrent setImmediate, 0 arguments
+// Concurrent setImmediate, 0 arguments
 function breadth(N) {
   var n = 0;
   bench.start();
@@ -71,7 +71,7 @@ function breadth(N) {
   }
 }
 
-// concurrent setImmediate, 1 argument
+// Concurrent setImmediate, 1 argument
 function breadth1(N) {
   var n = 0;
   bench.start();
@@ -85,7 +85,7 @@ function breadth1(N) {
   }
 }
 
-// concurrent setImmediate, 4 arguments
+// Concurrent setImmediate, 4 arguments
 function breadth4(N) {
   N /= 2;
   var n = 0;
diff --git a/doc/api/cluster.md b/doc/api/cluster.md
index 879f4af793e79c..90e64239b3b198 100644
--- a/doc/api/cluster.md
+++ b/doc/api/cluster.md
@@ -237,7 +237,7 @@ if (cluster.isMaster) {
     res.writeHead(200);
     res.end('hello world\n');
 
-    // notify master about the request
+    // Notify master about the request
     process.send({ cmd: 'notifyRequest' });
   }).listen(8000);
 }
diff --git a/doc/api/dgram.md b/doc/api/dgram.md
index bb492b56c2728a..2d44074df802ca 100644
--- a/doc/api/dgram.md
+++ b/doc/api/dgram.md
@@ -27,7 +27,7 @@ server.on('listening', () => {
 });
 
 server.bind(41234);
-// server listening 0.0.0.0:41234
+// Prints: server listening 0.0.0.0:41234
 ```
 
 ## Class: dgram.Socket
@@ -172,7 +172,7 @@ server.on('listening', () => {
 });
 
 server.bind(41234);
-// server listening 0.0.0.0:41234
+// Prints: server listening 0.0.0.0:41234
 ```
 
 ### socket.bind(options[, callback])
diff --git a/doc/api/domain.md b/doc/api/domain.md
index 0f53e958bd8976..226eb660f4b0bf 100644
--- a/doc/api/domain.md
+++ b/doc/api/domain.md
@@ -420,7 +420,7 @@ d.on('error', (er) => {
 });
 d.run(() => {
   process.nextTick(() => {
-    setTimeout(() => { // simulating some various async stuff
+    setTimeout(() => { // Simulating some various async stuff
       fs.open('non-existent file', 'r', (er, fd) => {
         if (er) throw er;
         // proceed...
diff --git a/doc/api/errors.md b/doc/api/errors.md
index a93a33b44eb401..498997408da0ea 100644
--- a/doc/api/errors.md
+++ b/doc/api/errors.md
@@ -158,7 +158,7 @@ const fs = require('fs');
 
 try {
   fs.readFile('/some/file/that/does-not-exist', (err, data) => {
-    // mistaken assumption: throwing here...
+    // Mistaken assumption: throwing here...
     if (err) {
       throw err;
     }
@@ -217,7 +217,7 @@ a string representing the location in the code at which
 ```js
 const myObject = {};
 Error.captureStackTrace(myObject);
-myObject.stack;  // similar to `new Error().stack`
+myObject.stack;  // Similar to `new Error().stack`
 ```
 
 The first line of the trace will be prefixed with
@@ -316,7 +316,7 @@ will not be present in the stack traces:
 const cheetahify = require('./native-binding.node');
 
 function makeFaster() {
-  // cheetahify *synchronously* calls speedy.
+  // `cheetahify()` *synchronously* calls speedy.
   cheetahify(function speedy() {
     throw new Error('oh no!');
   });
diff --git a/doc/api/fs.md b/doc/api/fs.md
index b5fd6702f6fbd4..5df0c5a5bfda2e 100644
--- a/doc/api/fs.md
+++ b/doc/api/fs.md
@@ -1908,7 +1908,7 @@ console.log(fs.readFileSync('temp.txt', 'utf8'));
 // get the file descriptor of the file to be truncated
 const fd = fs.openSync('temp.txt', 'r+');
 
-// truncate the file to first four bytes
+// Truncate the file to first four bytes
 fs.ftruncate(fd, 4, (err) => {
   assert.ifError(err);
   console.log(fs.readFileSync('temp.txt', 'utf8'));
@@ -3899,7 +3899,7 @@ async function doTruncate() {
     await filehandle.truncate(4);
   } finally {
     if (filehandle) {
-      // close the file if it is opened.
+      // Close the file if it is opened.
       await filehandle.close();
     }
   }
@@ -3926,7 +3926,7 @@ async function doTruncate() {
     await filehandle.truncate(10);
   } finally {
     if (filehandle) {
-      // close the file if it is opened.
+      // Close the file if it is opened.
       await filehandle.close();
     }
   }
diff --git a/doc/api/http.md b/doc/api/http.md
index dc2383aabd9bcf..7c4f09fd364f1b 100644
--- a/doc/api/http.md
+++ b/doc/api/http.md
@@ -373,7 +373,7 @@ proxy.on('connect', (req, cltSocket, head) => {
 // now that proxy is running
 proxy.listen(1337, '127.0.0.1', () => {
 
-  // make a request to a tunneling proxy
+  // Make a request to a tunneling proxy
   const options = {
     port: 1337,
     host: '127.0.0.1',
@@ -387,7 +387,7 @@ proxy.listen(1337, '127.0.0.1', () => {
   req.on('connect', (res, socket, head) => {
     console.log('got connected!');
 
-    // make a request over an HTTP tunnel
+    // Make a request over an HTTP tunnel
     socket.write('GET / HTTP/1.1\r\n' +
                  'Host: www.google.com:80\r\n' +
                  'Connection: close\r\n' +
@@ -1307,7 +1307,7 @@ with any headers passed to [`response.writeHead()`][], with the headers passed
 to [`response.writeHead()`][] given precedence.
 
 ```js
-// returns content-type = text/plain
+// Returns content-type = text/plain
 const server = http.createServer((req, res) => {
   res.setHeader('Content-Type', 'text/html');
   res.setHeader('X-Foo', 'bar');
@@ -1500,7 +1500,7 @@ desired with potential future retrieval and modification, use
 [`response.setHeader()`][] instead.
 
 ```js
-// returns content-type = text/plain
+// Returns content-type = text/plain
 const server = http.createServer((req, res) => {
   res.setHeader('Content-Type', 'text/html');
   res.setHeader('X-Foo', 'bar');
@@ -1912,7 +1912,7 @@ http.get('http://nodejs.org/dist/index.json', (res) => {
   }
   if (error) {
     console.error(error.message);
-    // consume response data to free up memory
+    // Consume response data to free up memory
     res.resume();
     return;
   }
diff --git a/doc/api/http2.md b/doc/api/http2.md
index ac4385ba110a42..434f603201b844 100644
--- a/doc/api/http2.md
+++ b/doc/api/http2.md
@@ -3138,7 +3138,7 @@ with any headers passed to [`response.writeHead()`][], with the headers passed
 to [`response.writeHead()`][] given precedence.
 
 ```js
-// returns content-type = text/plain
+// Returns content-type = text/plain
 const server = http2.createServer((req, res) => {
   res.setHeader('Content-Type', 'text/html');
   res.setHeader('X-Foo', 'bar');
@@ -3332,7 +3332,7 @@ with any headers passed to [`response.writeHead()`][], with the headers passed
 to [`response.writeHead()`][] given precedence.
 
 ```js
-// returns content-type = text/plain
+// Returns content-type = text/plain
 const server = http2.createServer((req, res) => {
   res.setHeader('Content-Type', 'text/html');
   res.setHeader('X-Foo', 'bar');
diff --git a/doc/api/inspector.md b/doc/api/inspector.md
index 0a11f6a1ff12eb..f32f6c3032b9d5 100644
--- a/doc/api/inspector.md
+++ b/doc/api/inspector.md
@@ -171,7 +171,7 @@ session.post('Profiler.enable', () => {
 
     // some time later...
     session.post('Profiler.stop', (err, { profile }) => {
-      // write profile to disk, upload, etc.
+      // Write profile to disk, upload, etc.
       if (!err) {
         fs.writeFileSync('./profile.cpuprofile', JSON.stringify(profile));
       }
diff --git a/doc/api/modules.md b/doc/api/modules.md
index 222cf71f35c5ca..5ef61141a6353c 100644
--- a/doc/api/modules.md
+++ b/doc/api/modules.md
@@ -921,7 +921,7 @@ added: v10.12.0
 const { createRequireFromPath } = require('module');
 const requireUtil = createRequireFromPath('../src/utils');
 
-// require `../src/utils/some-tool`
+// Require `../src/utils/some-tool`
 requireUtil('./some-tool');
 ```
 
diff --git a/doc/api/net.md b/doc/api/net.md
index 4cc741f7d4a1fb..eae4e74223a11b 100644
--- a/doc/api/net.md
+++ b/doc/api/net.md
@@ -132,7 +132,7 @@ const server = net.createServer((socket) => {
   throw err;
 });
 
-// grab an arbitrary unused port.
+// Grab an arbitrary unused port.
 server.listen(() => {
   console.log('opened server on', server.address());
 });
diff --git a/doc/api/perf_hooks.md b/doc/api/perf_hooks.md
index 687cdae3aa3244..666734cf14cc62 100644
--- a/doc/api/perf_hooks.md
+++ b/doc/api/perf_hooks.md
@@ -331,7 +331,7 @@ const {
 } = require('perf_hooks');
 
 const obs = new PerformanceObserver((list, observer) => {
-  // Called three times synchronously. list contains one item
+  // Called three times synchronously. `list` contains one item.
 });
 obs.observe({ entryTypes: ['mark'] });
 
@@ -346,7 +346,7 @@ const {
 } = require('perf_hooks');
 
 const obs = new PerformanceObserver((list, observer) => {
-  // called once. list contains three items
+  // Called once. `list` contains three items.
 });
 obs.observe({ entryTypes: ['mark'], buffered: true });
 
diff --git a/doc/api/process.md b/doc/api/process.md
index 8e2e096bd3723c..b8d34f264d63ec 100644
--- a/doc/api/process.md
+++ b/doc/api/process.md
@@ -1286,7 +1286,7 @@ setTimeout(() => {
   // [ 1, 552 ]
 
   console.log(`Benchmark took ${diff[0] * NS_PER_SEC + diff[1]} nanoseconds`);
-  // benchmark took 1000000552 nanoseconds
+  // Benchmark took 1000000552 nanoseconds
 }, 1000);
 ```
 
diff --git a/doc/api/readline.md b/doc/api/readline.md
index 56a5254adcc238..4db4b0f899cae6 100644
--- a/doc/api/readline.md
+++ b/doc/api/readline.md
@@ -457,7 +457,7 @@ For instance: `[[substr1, substr2, ...], originalsubstring]`.
 function completer(line) {
   const completions = '.help .error .exit .quit .q'.split(' ');
   const hits = completions.filter((c) => c.startsWith(line));
-  // show all completions if none found
+  // Show all completions if none found
   return [hits.length ? hits : completions, line];
 }
 ```
diff --git a/doc/api/stream.md b/doc/api/stream.md
index c9d4b035ddd48c..bff9ee06836ca7 100644
--- a/doc/api/stream.md
+++ b/doc/api/stream.md
@@ -256,8 +256,8 @@ function writeOneMillionTimes(writer, data, encoding, callback) {
         // last time!
         writer.write(data, encoding, callback);
       } else {
-        // see if we should continue, or wait
-        // don't pass the callback, because we're not done yet.
+        // See if we should continue, or wait.
+        // Don't pass the callback, because we're not done yet.
         ok = writer.write(data, encoding);
       }
     } while (i > 0 && ok);
@@ -418,7 +418,7 @@ const fs = require('fs');
 const file = fs.createWriteStream('example.txt');
 file.write('hello, ');
 file.end('world!');
-// writing more now is not allowed!
+// Writing more now is not allowed!
 ```
 
 ##### writable.setDefaultEncoding(encoding)
@@ -819,7 +819,7 @@ cause some amount of data to be read into an internal buffer.
 ```javascript
 const readable = getReadableStreamSomehow();
 readable.on('readable', function() {
-  // there is some data to read now
+  // There is some data to read now
   let data;
 
   while (data = this.read()) {
@@ -2431,7 +2431,7 @@ net.createServer((socket) => {
     socket.end('The message was received but was not processed.\n');
   });
 
-  // start the flow of data, discarding it.
+  // Start the flow of data, discarding it.
   socket.resume();
 }).listen(1337);
 ```
diff --git a/lib/_http_agent.js b/lib/_http_agent.js
index 17f6856bc703ad..8632da45726514 100644
--- a/lib/_http_agent.js
+++ b/lib/_http_agent.js
@@ -162,7 +162,7 @@ Agent.prototype.addRequest = function addRequest(req, options, port/* legacy */,
   var sockLen = freeLen + this.sockets[name].length;
 
   if (freeLen) {
-    // we have a free socket, so use that.
+    // We have a free socket, so use that.
     var socket = this.freeSockets[name].shift();
     // Guard against an uninitialized or user supplied Socket.
     if (socket._handle && typeof socket._handle.asyncReset === 'function') {
@@ -357,7 +357,7 @@ function setRequestSocket(agent, req, socket) {
     return;
   }
   socket.setTimeout(req.timeout);
-  // reset timeout after response end
+  // Reset timeout after response end
   req.once('response', (res) => {
     res.once('end', () => {
       if (socket.timeout !== agentTimeout) {
diff --git a/lib/_http_common.js b/lib/_http_common.js
index 7ecef8b83d412b..a83c82c9d4b292 100644
--- a/lib/_http_common.js
+++ b/lib/_http_common.js
@@ -147,7 +147,7 @@ function parserOnMessageComplete() {
     stream.push(null);
   }
 
-  // force to read the next incoming message
+  // Force to read the next incoming message
   readStart(parser.socket);
 }
 
diff --git a/lib/_http_server.js b/lib/_http_server.js
index adf2543cfe0bc5..7a2675961806a7 100644
--- a/lib/_http_server.js
+++ b/lib/_http_server.js
@@ -594,7 +594,7 @@ function resOnFinish(req, res, socket, state, server) {
       state.keepAliveTimeoutSet = true;
     }
   } else {
-    // start sending the next message
+    // Start sending the next message
     var m = state.outgoing.shift();
     if (m) {
       m.assignSocket(socket);
diff --git a/lib/_stream_duplex.js b/lib/_stream_duplex.js
index 7551af7f4e7f0f..83aac732e94d82 100644
--- a/lib/_stream_duplex.js
+++ b/lib/_stream_duplex.js
@@ -124,7 +124,7 @@ Object.defineProperty(Duplex.prototype, 'destroyed', {
     return this._readableState.destroyed && this._writableState.destroyed;
   },
   set(value) {
-    // we ignore the value if the stream
+    // We ignore the value if the stream
     // has not been initialized yet
     if (this._readableState === undefined ||
         this._writableState === undefined) {
diff --git a/lib/_stream_readable.js b/lib/_stream_readable.js
index b3a1e1933a743b..4e162b97f77f2b 100644
--- a/lib/_stream_readable.js
+++ b/lib/_stream_readable.js
@@ -182,7 +182,7 @@ Object.defineProperty(Readable.prototype, 'destroyed', {
     return this._readableState.destroyed;
   },
   set(value) {
-    // we ignore the value if the stream
+    // We ignore the value if the stream
     // has not been initialized yet
     if (!this._readableState) {
       return;
@@ -600,7 +600,7 @@ function maybeReadMore_(stream, state) {
     debug('maybeReadMore read 0');
     stream.read(0);
     if (len === state.length)
-      // didn't get any data, stop spinning.
+      // Didn't get any data, stop spinning.
       break;
   }
   state.readingMore = false;
@@ -741,7 +741,7 @@ Readable.prototype.pipe = function(dest, pipeOpts) {
     src.unpipe(dest);
   }
 
-  // tell the dest that it's being piped to
+  // Tell the dest that it's being piped to
   dest.emit('pipe', src);
 
   // Start the flow if it hasn't been started already.
@@ -793,7 +793,7 @@ Readable.prototype.unpipe = function(dest) {
     return this;
   }
 
-  // slow case. multiple pipe destinations.
+  // Slow case with multiple pipe destinations.
 
   if (!dest) {
     // remove all.
@@ -896,7 +896,7 @@ function updateReadableListening(self) {
     // the upcoming resume will not flow.
     state.flowing = true;
 
-    // crude way to check if we should resume
+    // Crude way to check if we should resume
   } else if (self.listenerCount('data') > 0) {
     self.resume();
   }
@@ -1008,7 +1008,7 @@ Readable.prototype.wrap = function(stream) {
     }
   }
 
-  // proxy certain important events.
+  // Proxy certain important events.
   for (var n = 0; n < kProxyEvents.length; n++) {
     stream.on(kProxyEvents[n], this.emit.bind(this, kProxyEvents[n]));
   }
@@ -1070,7 +1070,7 @@ Object.defineProperty(Readable.prototype, 'readableFlowing', {
   }
 });
 
-// exposed for testing purposes only.
+// Exposed for testing purposes only.
 Readable._fromList = fromList;
 
 Object.defineProperty(Readable.prototype, 'readableLength', {
@@ -1096,7 +1096,7 @@ function fromList(n, state) {
   if (state.objectMode)
     ret = state.buffer.shift();
   else if (!n || n >= state.length) {
-    // read it all, truncate the list
+    // Read it all, truncate the list
     if (state.decoder)
       ret = state.buffer.join('');
     else if (state.buffer.length === 1)
diff --git a/lib/_stream_writable.js b/lib/_stream_writable.js
index 4c60bf7d7a1bac..e5b11d06a19b39 100644
--- a/lib/_stream_writable.js
+++ b/lib/_stream_writable.js
@@ -434,7 +434,7 @@ function onwriteError(stream, state, sync, er, cb) {
     cb(er);
     stream._writableState.errorEmitted = true;
     errorOrDestroy(stream, er);
-    // this can emit finish, but finish must
+    // This can emit finish, but finish must
     // always follow error
     finishMaybe(stream, state);
   }
@@ -589,7 +589,7 @@ Writable.prototype.end = function(chunk, encoding, cb) {
     this.uncork();
   }
 
-  // ignore unnecessary end() calls.
+  // Ignore unnecessary end() calls.
   if (!state.ending)
     endWritable(this, state, cb);
 
@@ -697,7 +697,7 @@ Object.defineProperty(Writable.prototype, 'destroyed', {
     return this._writableState.destroyed;
   },
   set(value) {
-    // we ignore the value if the stream
+    // We ignore the value if the stream
     // has not been initialized yet
     if (!this._writableState) {
       return;
diff --git a/lib/dgram.js b/lib/dgram.js
index e48c117eed134b..ceda82653085df 100644
--- a/lib/dgram.js
+++ b/lib/dgram.js
@@ -293,7 +293,7 @@ Socket.prototype.bind = function(port_, address_ /* , callback */) {
       });
     } else {
       if (!state.handle)
-        return; // handle has been closed in the mean time
+        return; // Handle has been closed in the mean time
 
       const err = state.handle.bind(ip, port || 0, flags);
       if (err) {
diff --git a/lib/domain.js b/lib/domain.js
index 76b27dc058e8c2..24cc4061326ee0 100644
--- a/lib/domain.js
+++ b/lib/domain.js
@@ -286,7 +286,7 @@ Domain.prototype.exit = function() {
   var index = stack.lastIndexOf(this);
   if (index === -1) return;
 
-  // exit all domains until this one.
+  // Exit all domains until this one.
   stack.splice(index);
 
   exports.active = stack[stack.length - 1];
@@ -301,7 +301,7 @@ Domain.prototype.add = function(ee) {
   if (ee.domain === this)
     return;
 
-  // has a domain already - remove it first.
+  // Has a domain already - remove it first.
   if (ee.domain)
     ee.domain.remove(ee);
 
diff --git a/lib/fs.js b/lib/fs.js
index e8ba400a4b1de1..e5abc59b591d22 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -368,7 +368,7 @@ function readFileSync(path, options) {
     } while (bytesRead !== 0 && pos < size);
   } else {
     do {
-      // the kernel lies about many files.
+      // The kernel lies about many files.
       // Go ahead and try to read some bytes.
       buffer = Buffer.allocUnsafe(8192);
       bytesRead = tryReadSync(fd, isUserFd, buffer, 0, 8192);
@@ -1414,7 +1414,7 @@ function realpathSync(p, options) {
   const knownHard = Object.create(null);
   const original = p;
 
-  // current character position in p
+  // Current character position in p
   let pos;
   // The partial path so far, including a trailing slash if any
   let current;
@@ -1481,7 +1481,7 @@ function realpathSync(p, options) {
         continue;
       }
 
-      // read the link if it wasn't read before
+      // Read the link if it wasn't read before
       // dev/ino always return 0 on windows, so skip the check.
       let linkTarget = null;
       let id;
@@ -1506,7 +1506,7 @@ function realpathSync(p, options) {
       if (!isWindows) seenLinks[id] = linkTarget;
     }
 
-    // resolve the link, then start over
+    // Resolve the link, then start over
     p = pathModule.resolve(resolvedLink, p.slice(pos));
 
     // Skip over roots
@@ -1554,7 +1554,7 @@ function realpath(p, options, callback) {
   const seenLinks = Object.create(null);
   const knownHard = Object.create(null);
 
-  // current character position in p
+  // Current character position in p
   let pos;
   // The partial path so far, including a trailing slash if any
   let current;
@@ -1580,7 +1580,7 @@ function realpath(p, options, callback) {
   // Walk down the path, swapping out linked path parts for their real
   // values
   function LOOP() {
-    // stop if scanned past end of path
+    // Stop if scanned past end of path
     if (pos >= p.length) {
       return callback(null, encodeRealpathResult(p, options));
     }
@@ -1620,9 +1620,9 @@ function realpath(p, options, callback) {
       return process.nextTick(LOOP);
     }
 
-    // stat & read the link if not read before
-    // call gotTarget as soon as the link target is known
-    // dev/ino always return 0 on windows, so skip the check.
+    // Stat & read the link if not read before.
+    // Call `gotTarget()` as soon as the link target is known.
+    // `dev`/`ino` always return 0 on windows, so skip the check.
     let id;
     if (!isWindows) {
       const dev = stats.dev.toString(32);
@@ -1649,7 +1649,7 @@ function realpath(p, options, callback) {
   }
 
   function gotResolvedLink(resolvedLink) {
-    // resolve the link, then start over
+    // Resolve the link, then start over
     p = pathModule.resolve(resolvedLink, p.slice(pos));
     current = base = splitRoot(p);
     pos = current.length;
diff --git a/lib/internal/child_process.js b/lib/internal/child_process.js
index 4414b002ae0fea..be90d23f2a3203 100644
--- a/lib/internal/child_process.js
+++ b/lib/internal/child_process.js
@@ -97,7 +97,7 @@ const handleConversion = {
       if (!socket._handle)
         return;
 
-      // if the socket was created by net.Server
+      // If the socket was created by net.Server
       if (socket.server) {
         // The worker should keep track of the socket
         message.key = socket.server._connectionKey;
@@ -169,7 +169,7 @@ const handleConversion = {
       // If the socket was created by net.Server we will track the socket
       if (message.key) {
 
-        // add socket to connections list
+        // Add socket to connections list
         var socketList = getSocketList('got', this, message.key);
         socketList.add({
           socket: socket
@@ -561,7 +561,7 @@ function setupChannel(target, channel) {
     }
   };
 
-  // object where socket lists will live
+  // Object where socket lists will live
   channel.sockets = { got: {}, send: {} };
 
   // handlers will go through this
@@ -670,7 +670,7 @@ function setupChannel(target, channel) {
       options = { swallowErrors: options };
     }
 
-    // package messages with a handle object
+    // Package messages with a handle object
     if (handle) {
       // This message will be handled by an internalMessage event handler
       message = {
diff --git a/lib/internal/fs/utils.js b/lib/internal/fs/utils.js
index fb36a173c3bff5..8a9d4d357204ec 100644
--- a/lib/internal/fs/utils.js
+++ b/lib/internal/fs/utils.js
@@ -393,7 +393,7 @@ function toUnixTimestamp(time, name = 'time') {
     return time;
   }
   if (util.isDate(time)) {
-    // convert to 123.456 UNIX timestamp
+    // Convert to 123.456 UNIX timestamp
     return time.getTime() / 1000;
   }
   throw new ERR_INVALID_ARG_TYPE(name, ['Date', 'Time in seconds'], time);
diff --git a/lib/internal/fs/watchers.js b/lib/internal/fs/watchers.js
index 7bc6f2ac97365a..a785b8ded86d1c 100644
--- a/lib/internal/fs/watchers.js
+++ b/lib/internal/fs/watchers.js
@@ -118,7 +118,7 @@ function FSWatcher() {
       if (this._handle !== null) {
         // We don't use this.close() here to avoid firing the close event.
         this._handle.close();
-        this._handle = null;  // make the handle garbage collectable
+        this._handle = null;  // Make the handle garbage collectable
       }
       const error = errors.uvException({
         errno: status,
@@ -185,7 +185,7 @@ FSWatcher.prototype.close = function() {
     return;
   }
   this._handle.close();
-  this._handle = null;  // make the handle garbage collectable
+  this._handle = null;  // Make the handle garbage collectable
   process.nextTick(emitCloseNT, this);
 };
 
diff --git a/lib/internal/http2/compat.js b/lib/internal/http2/compat.js
index 286bc51683e494..cad6efc7337eb1 100644
--- a/lib/internal/http2/compat.js
+++ b/lib/internal/http2/compat.js
@@ -130,7 +130,7 @@ function onStreamEnd() {
 }
 
 function onStreamError(error) {
-  // this is purposefully left blank
+  // This is purposefully left blank
   //
   // errors in compatibility mode are
   // not forwarded to the request
diff --git a/lib/internal/http2/core.js b/lib/internal/http2/core.js
index 21f780c733d931..c17980993a9270 100644
--- a/lib/internal/http2/core.js
+++ b/lib/internal/http2/core.js
@@ -1732,7 +1732,7 @@ class Http2Stream extends Duplex {
     this.emit('timeout');
   }
 
-  // true if the HEADERS frame has been sent
+  // True if the HEADERS frame has been sent
   get headersSent() {
     return !!(this[kState].flags & STREAM_FLAGS_HEADERS_SENT);
   }
@@ -1742,7 +1742,7 @@ class Http2Stream extends Duplex {
     return !!(this[kState].flags & STREAM_FLAGS_ABORTED);
   }
 
-  // true if dealing with a HEAD request
+  // True if dealing with a HEAD request
   get headRequest() {
     return !!(this[kState].flags & STREAM_FLAGS_HEAD_REQUEST);
   }
diff --git a/lib/internal/modules/cjs/loader.js b/lib/internal/modules/cjs/loader.js
index def440da63c41c..f5dff9b5c11803 100644
--- a/lib/internal/modules/cjs/loader.js
+++ b/lib/internal/modules/cjs/loader.js
@@ -335,7 +335,7 @@ Module._findPath = function(request, paths, isMain) {
       }
 
       if (!filename) {
-        // try it with each of the extensions
+        // Try it with each of the extensions
         if (exts === undefined)
           exts = Object.keys(Module._extensions);
         filename = tryExtensions(basePath, exts, isMain);
@@ -378,7 +378,7 @@ var nmLen = nmChars.length;
 if (isWindows) {
   // 'from' is the __dirname of the module.
   Module._nodeModulePaths = function(from) {
-    // guarantee that 'from' is absolute.
+    // Guarantee that 'from' is absolute.
     from = path.resolve(from);
 
     // note: this approach *only* works when the path is guaranteed
@@ -422,7 +422,7 @@ if (isWindows) {
 } else { // posix
   // 'from' is the __dirname of the module.
   Module._nodeModulePaths = function(from) {
-    // guarantee that 'from' is absolute.
+    // Guarantee that 'from' is absolute.
     from = path.resolve(from);
     // Return early not only to avoid unnecessary work, but to *avoid* returning
     // an array of two items for a root: [ '//node_modules', '/node_modules' ]
@@ -836,7 +836,7 @@ Module._extensions['.node'] = function(module, filename) {
     const moduleURL = pathToFileURL(filename);
     manifest.assertIntegrity(moduleURL, content);
   }
-  // be aware this doesn't use `content`
+  // Be aware this doesn't use `content`
   return process.dlopen(module, path.toNamespacedPath(filename));
 };
 
diff --git a/lib/internal/readline.js b/lib/internal/readline.js
index f1716f1f25824f..b05c2d575a31dc 100644
--- a/lib/internal/readline.js
+++ b/lib/internal/readline.js
@@ -244,7 +244,7 @@ function* emitKeys(stream) {
          */
         const cmdStart = s.length - 1;
 
-        // skip one or two leading digits
+        // Skip one or two leading digits
         if (ch >= '0' && ch <= '9') {
           s += (ch = yield);
 
@@ -386,7 +386,7 @@ function* emitKeys(stream) {
       // carriage return
       key.name = 'return';
     } else if (ch === '\n') {
-      // enter, should have been called linefeed
+      // Enter, should have been called linefeed
       key.name = 'enter';
     } else if (ch === '\t') {
       // tab
diff --git a/lib/internal/stream_base_commons.js b/lib/internal/stream_base_commons.js
index 31291e751d57a6..9c3b60e584c033 100644
--- a/lib/internal/stream_base_commons.js
+++ b/lib/internal/stream_base_commons.js
@@ -162,7 +162,7 @@ function onStreamRead(arrayBuffer) {
     return stream.destroy(errnoException(nread, 'read'));
   }
 
-  // defer this until we actually emit end
+  // Defer this until we actually emit end
   if (stream._readableState.endEmitted) {
     if (stream[kMaybeDestroy])
       stream[kMaybeDestroy]();
@@ -170,7 +170,7 @@ function onStreamRead(arrayBuffer) {
     if (stream[kMaybeDestroy])
       stream.on('end', stream[kMaybeDestroy]);
 
-    // push a null to signal the end of data.
+    // Push a null to signal the end of data.
     // Do it before `maybeDestroy` for correct order of events:
     // `end` -> `close`
     stream.push(null);
diff --git a/lib/internal/streams/async_iterator.js b/lib/internal/streams/async_iterator.js
index 810132c0cb2c86..0d22e4efeec99c 100644
--- a/lib/internal/streams/async_iterator.js
+++ b/lib/internal/streams/async_iterator.js
@@ -85,10 +85,9 @@ const ReadableStreamAsyncIteratorPrototype = Object.setPrototypeOf({
       });
     }
 
-    // if we have multiple next() calls
-    // we will wait for the previous Promise to finish
-    // this logic is optimized to support for await loops,
-    // where next() is only called once at a time
+    // If we have multiple next() calls we will wait for the previous Promise to
+    // finish. This logic is optimized to support for await loops, where next()
+    // is only called once at a time.
     const lastPromise = this[kLastPromise];
     let promise;
 
@@ -96,7 +95,7 @@ const ReadableStreamAsyncIteratorPrototype = Object.setPrototypeOf({
       promise = new Promise(wrapForNext(lastPromise, this));
     } else {
       // Fast path needed to support multiple this.push()
-      // without triggering the next() queue
+      // without triggering the next() queue.
       const data = this[kStream].read();
       if (data !== null) {
         return Promise.resolve(createIterResult(data, false));
@@ -136,7 +135,7 @@ const createReadableStreamAsyncIterator = (stream) => {
       value: stream._readableState.endEmitted,
       writable: true
     },
-    // the function passed to new Promise
+    // The function passed to new Promise
     // is cached so we avoid allocating a new
     // closure at every run
     [kHandlePromise]: {
diff --git a/lib/net.js b/lib/net.js
index e46dea49282c73..2af6fedfd39d6d 100644
--- a/lib/net.js
+++ b/lib/net.js
@@ -535,7 +535,7 @@ Socket.prototype._read = function(n) {
     debug('_read wait for connection');
     this.once('connect', () => this._read(n));
   } else if (!this._handle.reading) {
-    // not already reading, start the flow
+    // Not already reading, start the flow
     debug('Socket._read readStart');
     this._handle.reading = true;
     var err = this._handle.readStart();
@@ -1049,7 +1049,7 @@ Socket.prototype.unref = function() {
 function afterConnect(status, handle, req, readable, writable) {
   var self = handle[owner_symbol];
 
-  // callback may come after call to destroy
+  // Callback may come after call to destroy
   if (self.destroyed) {
     return;
   }
diff --git a/lib/readline.js b/lib/readline.js
index 46fc3047709915..585128fe02697c 100644
--- a/lib/readline.js
+++ b/lib/readline.js
@@ -768,7 +768,7 @@ Interface.prototype._moveCursor = function(dx) {
 
   var newPos = this._getCursorPos();
 
-  // check if cursors are in the same line
+  // Check if cursors are in the same line
   if (oldPos.rows === newPos.rows) {
     var diffCursor = this.cursor - oldcursor;
     var diffWidth;
@@ -837,11 +837,11 @@ Interface.prototype._ttyWrite = function(s, key) {
         }
         break;
 
-      case 'u': // delete from current to start of line
+      case 'u': // Delete from current to start of line
         this._deleteLineLeft();
         break;
 
-      case 'k': // delete from current to end of line
+      case 'k': // Delete from current to end of line
         this._deleteLineRight();
         break;
 
@@ -901,12 +901,12 @@ Interface.prototype._ttyWrite = function(s, key) {
         }
         break;
 
-      case 'w': // delete backwards to a word boundary
+      case 'w': // Delete backwards to a word boundary
       case 'backspace':
         this._deleteWordLeft();
         break;
 
-      case 'delete': // delete forward to a word boundary
+      case 'delete': // Delete forward to a word boundary
         this._deleteWordRight();
         break;
 
@@ -936,7 +936,7 @@ Interface.prototype._ttyWrite = function(s, key) {
         this._deleteWordRight();
         break;
 
-      case 'backspace': // delete backwards to a word boundary
+      case 'backspace': // Delete backwards to a word boundary
         this._deleteWordLeft();
         break;
     }
@@ -972,7 +972,7 @@ Interface.prototype._ttyWrite = function(s, key) {
         break;
 
       case 'left':
-        // obtain the code point to the left
+        // Obtain the code point to the left
         this._moveCursor(-charLengthLeft(this.line, this.cursor));
         break;
 
diff --git a/lib/sys.js b/lib/sys.js
index 87f40fc6d5f1f0..1292a38e9ced07 100644
--- a/lib/sys.js
+++ b/lib/sys.js
@@ -21,9 +21,8 @@
 
 'use strict';
 
-// the sys module was renamed to 'util'.
-// this shim remains to keep old programs working.
-// sys is deprecated and shouldn't be used
+// The sys module was renamed to 'util'. This shim remains to keep old programs
+// working. `sys` is deprecated and shouldn't be used.
 
 module.exports = require('util');
 process.emitWarning('sys is deprecated. Use util instead.',
diff --git a/lib/url.js b/lib/url.js
index 78dcbe713010e9..391d6c2723d99d 100644
--- a/lib/url.js
+++ b/lib/url.js
@@ -80,12 +80,12 @@ const unsafeProtocol = new SafeSet([
   'javascript',
   'javascript:'
 ]);
-// protocols that never have a hostname.
+// Protocols that never have a hostname.
 const hostlessProtocol = new SafeSet([
   'javascript',
   'javascript:'
 ]);
-// protocols that always contain a // bit.
+// Protocols that always contain a // bit.
 const slashedProtocol = new SafeSet([
   'http',
   'http:',
@@ -367,7 +367,7 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
     if (this.hostname.length > hostnameMaxLen) {
       this.hostname = '';
     } else {
-      // hostnames are always lower case.
+      // Hostnames are always lower case.
       this.hostname = this.hostname.toLowerCase();
     }
 
@@ -396,8 +396,8 @@ Url.prototype.parse = function parse(url, parseQueryString, slashesDenoteHost) {
     }
   }
 
-  // now rest is set to the post-host stuff.
-  // chop off any delim chars.
+  // Now rest is set to the post-host stuff.
+  // Chop off any delim chars.
   if (!unsafeProtocol.has(lowerProto)) {
     // First, make 100% sure that any "autoEscape" chars get
     // escaped, even if encodeURIComponent doesn't think they
@@ -810,7 +810,7 @@ Url.prototype.resolveObject = function resolveObject(relative) {
     result.search = relative.search;
     result.query = relative.query;
     srcPath = relPath;
-    // fall through to the dot-handling below.
+    // Fall through to the dot-handling below.
   } else if (relPath.length) {
     // it's relative
     // throw away the existing file, and take the new path instead.
diff --git a/lib/zlib.js b/lib/zlib.js
index 3bc82e36a82d1d..09c3419b4d0b7c 100644
--- a/lib/zlib.js
+++ b/lib/zlib.js
@@ -61,7 +61,7 @@ const {
   BROTLI_OPERATION_FINISH
 } = constants;
 
-// translation table for return codes.
+// Translation table for return codes.
 const codes = {
   Z_OK: constants.Z_OK,
   Z_STREAM_END: constants.Z_STREAM_END,
@@ -153,8 +153,8 @@ function zlibBufferSync(engine, buffer) {
 
 function zlibOnError(message, errno, code) {
   var self = this[owner_symbol];
-  // there is no way to cleanly recover.
-  // continuing only obscures problems.
+  // There is no way to cleanly recover.
+  // Continuing only obscures problems.
   _close(self);
   self._hadError = true;
 
diff --git a/test/async-hooks/test-graph.signal.js b/test/async-hooks/test-graph.signal.js
index 4c5b857fc2e08f..c2f889e7b02569 100644
--- a/test/async-hooks/test-graph.signal.js
+++ b/test/async-hooks/test-graph.signal.js
@@ -23,10 +23,10 @@ function onsigusr2() {
   count++;
 
   if (count === 1) {
-    // trigger same signal handler again
+    // Trigger same signal handler again
     exec(`kill -USR2 ${process.pid}`);
   } else {
-    // install another signal handler
+    // Install another signal handler
     process.removeAllListeners('SIGUSR2');
     process.on('SIGUSR2', common.mustCall(onsigusr2Again));
 
diff --git a/test/async-hooks/test-promise.promise-before-init-hooks.js b/test/async-hooks/test-promise.promise-before-init-hooks.js
index 0f74c968e6a25e..51787b8065a71b 100644
--- a/test/async-hooks/test-promise.promise-before-init-hooks.js
+++ b/test/async-hooks/test-promise.promise-before-init-hooks.js
@@ -9,7 +9,7 @@ const p = new Promise(common.mustCall(function executor(resolve) {
   resolve(5);
 }));
 
-// init hooks after promise was created
+// Init hooks after promise was created
 const hooks = initHooks({ allowNoInit: true });
 hooks.enable();
 
diff --git a/test/async-hooks/test-signalwrap.js b/test/async-hooks/test-signalwrap.js
index 5bc02e6dc46204..b906355af707cc 100644
--- a/test/async-hooks/test-signalwrap.js
+++ b/test/async-hooks/test-signalwrap.js
@@ -42,7 +42,7 @@ function onsigusr2() {
       signal1, { init: 1, before: 1 },
       ' signal1: when first SIGUSR2 handler is called for the first time');
 
-    // trigger same signal handler again
+    // Trigger same signal handler again
     exec(`kill -USR2 ${process.pid}`);
   } else {
     // second invocation
@@ -50,7 +50,7 @@ function onsigusr2() {
       signal1, { init: 1, before: 2, after: 1 },
       'signal1: when first SIGUSR2 handler is called for the second time');
 
-    // install another signal handler
+    // Install another signal handler
     process.removeAllListeners('SIGUSR2');
     process.on('SIGUSR2', common.mustCall(onsigusr2Again));
 
diff --git a/test/async-hooks/test-tcpwrap.js b/test/async-hooks/test-tcpwrap.js
index a01a1fc4fe21d4..3256a1598b0adc 100644
--- a/test/async-hooks/test-tcpwrap.js
+++ b/test/async-hooks/test-tcpwrap.js
@@ -79,7 +79,7 @@ function ontcpConnection(serverConnection) {
     return;
   }
 
-  // only focusing on TCPCONNECTWRAP here
+  // Only focusing on TCPCONNECTWRAP here
   const tcpconnects = hooks.activitiesOfTypes('TCPCONNECTWRAP');
   assert.strictEqual(tcpconnects.length, 1);
   tcpconnect = tcpconnects[0];
diff --git a/test/common/index.js b/test/common/index.js
index 732d43f07aaeca..8076c287de7a99 100644
--- a/test/common/index.js
+++ b/test/common/index.js
@@ -821,7 +821,7 @@ module.exports = {
 
     const opensslCmd = spawnSync(opensslCli, ['version']);
     if (opensslCmd.status !== 0 || opensslCmd.error !== undefined) {
-      // openssl command cannot be executed
+      // OpenSSL command cannot be executed
       opensslCli = false;
     }
     return opensslCli;
diff --git a/test/es-module/test-esm-preserve-symlinks-main.js b/test/es-module/test-esm-preserve-symlinks-main.js
index 808b6c9a15f6fd..38ef5d8fcce6ad 100644
--- a/test/es-module/test-esm-preserve-symlinks-main.js
+++ b/test/es-module/test-esm-preserve-symlinks-main.js
@@ -50,7 +50,7 @@ function doTest(flags, done) {
   });
 }
 
-// first test the commonjs module loader
+// First test the commonjs module loader
 doTest([], () => {
   // now test the new loader
   doTest(['--experimental-modules'], () => {});
diff --git a/test/internet/test-dgram-broadcast-multi-process.js b/test/internet/test-dgram-broadcast-multi-process.js
index a989d687b0bdf4..a2b687bddb2347 100644
--- a/test/internet/test-dgram-broadcast-multi-process.js
+++ b/test/internet/test-dgram-broadcast-multi-process.js
@@ -167,7 +167,7 @@ if (process.argv[2] !== 'child') {
     reuseAddr: true
   });
 
-  // bind the address explicitly for sending
+  // Bind the address explicitly for sending
   // INADDR_BROADCAST to only one interface
   sendSocket.bind(common.PORT, bindAddress);
   sendSocket.on('listening', function() {
diff --git a/test/js-native-api/test_function/test.js b/test/js-native-api/test_function/test.js
index 6f0f1681752a2c..e89d64f61d172a 100644
--- a/test/js-native-api/test_function/test.js
+++ b/test/js-native-api/test_function/test.js
@@ -4,7 +4,7 @@
 const common = require('../../common');
 const assert = require('assert');
 
-// testing api calls for function
+// Testing api calls for function
 const test_function = require(`./build/${common.buildType}/test_function`);
 
 function func1() {
diff --git a/test/js-native-api/test_general/test.js b/test/js-native-api/test_general/test.js
index 720918f9645d99..f0be79085b6658 100644
--- a/test/js-native-api/test_general/test.js
+++ b/test/js-native-api/test_general/test.js
@@ -32,8 +32,7 @@ assert.strictEqual(test_general.testGetPrototype(extendedObject),
 assert.notStrictEqual(test_general.testGetPrototype(baseObject),
                       test_general.testGetPrototype(extendedObject));
 
-// test version management functions
-// expected version is currently 4
+// Test version management functions. The expected version is currently 4.
 assert.strictEqual(test_general.testGetVersion(), 4);
 
 [
@@ -91,7 +90,7 @@ assert.strictEqual(finalizeWasCalled, false,
                    ' test_general.finalizeWasCalled() ' +
                    `returned ${finalizeWasCalled}`);
 
-// test napi_adjust_external_memory
+// Test napi_adjust_external_memory
 const adjustedValue = test_general.testAdjustExternalMemory();
 assert.strictEqual(typeof adjustedValue, 'number');
 assert(adjustedValue > 0);
diff --git a/test/js-native-api/test_handle_scope/test.js b/test/js-native-api/test_handle_scope/test.js
index 53abfe178c8d7d..3935e1164092f2 100644
--- a/test/js-native-api/test_handle_scope/test.js
+++ b/test/js-native-api/test_handle_scope/test.js
@@ -2,7 +2,7 @@
 const common = require('../../common');
 const assert = require('assert');
 
-// testing handle scope api calls
+// Testing handle scope api calls
 const testHandleScope =
     require(`./build/${common.buildType}/test_handle_scope`);
 
diff --git a/test/js-native-api/test_properties/test.js b/test/js-native-api/test_properties/test.js
index 13a546c7b87f81..fa4cb587d6435a 100644
--- a/test/js-native-api/test_properties/test.js
+++ b/test/js-native-api/test_properties/test.js
@@ -33,7 +33,7 @@ assert.ok(!propertyNames.includes('readwriteAccessor2'));
 assert.ok(!propertyNames.includes('readonlyAccessor1'));
 assert.ok(!propertyNames.includes('readonlyAccessor2'));
 
-// validate property created with symbol
+// Validate property created with symbol
 const start = 'Symbol('.length;
 const end = start + 'NameKeySymbol'.length;
 const symbolDescription =
diff --git a/test/known_issues/test-dgram-bind-shared-ports-after-port-0.js b/test/known_issues/test-dgram-bind-shared-ports-after-port-0.js
index 703dd243760bb1..5ceac4ebeeb5ec 100644
--- a/test/known_issues/test-dgram-bind-shared-ports-after-port-0.js
+++ b/test/known_issues/test-dgram-bind-shared-ports-after-port-0.js
@@ -29,7 +29,7 @@ if (cluster.isMaster) {
     const worker2 = cluster.fork({ PRT1: msg.port1 });
     worker2.on('message', () => process.exit(0));
     worker2.on('exit', (code, signal) => {
-      // this is the droid we are looking for
+      // This is the droid we are looking for
       assert.strictEqual(code, 0);
       assert.strictEqual(signal, null);
     });
diff --git a/test/known_issues/test-inspector-cluster-port-clash.js b/test/known_issues/test-inspector-cluster-port-clash.js
index 0c5580530995a5..f5baedf8aa670b 100644
--- a/test/known_issues/test-inspector-cluster-port-clash.js
+++ b/test/known_issues/test-inspector-cluster-port-clash.js
@@ -29,7 +29,7 @@ function serialFork() {
   return new Promise((res) => {
     const worker = cluster.fork();
     worker.on('error', (err) => assert.fail(err));
-    // No common.mustCall since 1 out of 3 should fail
+    // No common.mustCall since 1 out of 3 should fail.
     worker.on('online', () => {
       worker.on('message', common.mustCall((message) => {
         ports.push(message.debugPort);
@@ -50,10 +50,10 @@ function serialFork() {
 if (cluster.isMaster) {
   cluster.on('online', common.mustCall((worker) => worker.send('dbgport'), 2));
 
-  // Block one of the ports with a listening socket
+  // Block one of the ports with a listening socket.
   const server = net.createServer();
   server.listen(clashPort, common.localhostIPv4, common.mustCall(() => {
-    // try to fork 3 workers No.2 should fail
+    // Try to fork 3 workers. No.2 should fail.
     Promise.all([serialFork(), serialFork(), serialFork()])
       .then(common.mustNotCall())
       .catch((err) => console.error(err));
diff --git a/test/message/throw_in_line_with_tabs.js b/test/message/throw_in_line_with_tabs.js
index fdc36b331ab8a1..ab059916b2c8da 100644
--- a/test/message/throw_in_line_with_tabs.js
+++ b/test/message/throw_in_line_with_tabs.js
@@ -26,7 +26,7 @@ require('../common');
 console.error('before');
 
 (function() {
-	// these lines should contain tab!
+	// These lines should contain tab!
 	// eslint-disable-next-line no-throw-literal
 	throw ({ foo: 'bar' });
 })();
diff --git a/test/message/v8_warning.js b/test/message/v8_warning.js
index e3394cdd7094e8..d7d1c5e7dbdff6 100644
--- a/test/message/v8_warning.js
+++ b/test/message/v8_warning.js
@@ -9,7 +9,7 @@ function AsmModule() {
     a = a | 0;
     b = b | 0;
 
-    // should be `return (a + b) | 0;`
+    // Should be `return (a + b) | 0;`
     return a + b;
   }
 
diff --git a/test/parallel/test-assert-deep.js b/test/parallel/test-assert-deep.js
index bd04bef701c23b..f9ac8d9a1f44ec 100644
--- a/test/parallel/test-assert-deep.js
+++ b/test/parallel/test-assert-deep.js
@@ -507,7 +507,7 @@ assertNotDeepOrStrict(
 
   m2.set(2, 'hi'); // different order
   m2.set(1, obj);
-  m2.set(3, [1, 2, 3]); // deep equal, but not reference equal.
+  m2.set(3, [1, 2, 3]); // Deep equal, but not reference equal.
 
   assertDeepAndStrictEqual(m1, m2);
 }
diff --git a/test/parallel/test-async-wrap-tlssocket-asyncreset.js b/test/parallel/test-async-wrap-tlssocket-asyncreset.js
index 983bce3b0239f2..e0dd8be2904429 100644
--- a/test/parallel/test-async-wrap-tlssocket-asyncreset.js
+++ b/test/parallel/test-async-wrap-tlssocket-asyncreset.js
@@ -52,7 +52,7 @@ server.listen(
               assert.strictEqual(res.statusCode, 200);
               res2.on('error', (err) => assert.fail(err));
               res2.socket.on('error', (err) => assert.fail(err));
-              // this should be the end of the test
+              // This should be the end of the test
               res2.destroy();
               server.close();
             })
diff --git a/test/parallel/test-buffer-alloc.js b/test/parallel/test-buffer-alloc.js
index 18f55837ab4b4d..3af09aee4c63fc 100644
--- a/test/parallel/test-buffer-alloc.js
+++ b/test/parallel/test-buffer-alloc.js
@@ -54,10 +54,10 @@ assert.strictEqual(d.length, 0);
 // Test invalid encoding for Buffer.toString
 assert.throws(() => b.toString('invalid'),
               /Unknown encoding: invalid/);
-// invalid encoding for Buffer.write
+// Invalid encoding for Buffer.write
 assert.throws(() => b.write('test string', 0, 5, 'invalid'),
               /Unknown encoding: invalid/);
-// unsupported arguments for Buffer.write
+// Unsupported arguments for Buffer.write
 assert.throws(() => b.write('test', 'utf8', 0),
               /is no longer supported/);
 
@@ -87,13 +87,13 @@ const outOfRangeError = {
 // Try to write a 0-length string beyond the end of b
 common.expectsError(() => b.write('', 2048), outOfBoundsError);
 
-// throw when writing to negative offset
+// Throw when writing to negative offset
 common.expectsError(() => b.write('a', -1), outOfBoundsError);
 
 // Throw when writing past bounds from the pool
 common.expectsError(() => b.write('a', 2048), outOfBoundsError);
 
-// throw when writing to negative offset
+// Throw when writing to negative offset
 common.expectsError(() => b.write('a', -1), outOfBoundsError);
 
 // Try to copy 0 bytes worth of data into an empty buffer
@@ -192,7 +192,7 @@ Buffer.alloc(1).write('', 1, 0);
 }
 
 {
-  // also from a non-pooled instance
+  // Also from a non-pooled instance
   const b = Buffer.allocUnsafeSlow(5);
   const c = b.slice(0, 4);
   const d = c.slice(0, 2);
@@ -390,7 +390,7 @@ assert.strictEqual(Buffer.from('KioqKioqKioqKioqKioqKioqKio=',
                                'base64').toString(),
                    '*'.repeat(20));
 
-// no padding, not a multiple of 4
+// No padding, not a multiple of 4
 assert.strictEqual(Buffer.from('Kg', 'base64').toString(), '*');
 assert.strictEqual(Buffer.from('Kio', 'base64').toString(), '*'.repeat(2));
 assert.strictEqual(Buffer.from('KioqKg', 'base64').toString(), '*'.repeat(4));
@@ -713,7 +713,7 @@ assert.strictEqual(x.inspect(), '<Buffer 81 a3 66 6f 6f a3 62 61 72>');
 }
 
 {
-  // test offset returns are correct
+  // Test offset returns are correct
   const b = Buffer.allocUnsafe(16);
   assert.strictEqual(b.writeUInt32LE(0, 0), 4);
   assert.strictEqual(b.writeUInt16LE(0, 4), 6);
@@ -819,7 +819,7 @@ common.expectsError(
   outOfRangeError
 );
 
-// test for common write(U)IntLE/BE
+// Test for common write(U)IntLE/BE
 {
   let buf = Buffer.allocUnsafe(3);
   buf.writeUIntLE(0x123456, 0, 3);
diff --git a/test/parallel/test-buffer-bytelength.js b/test/parallel/test-buffer-bytelength.js
index 3d419b316521e0..c0c7228d0d0b45 100644
--- a/test/parallel/test-buffer-bytelength.js
+++ b/test/parallel/test-buffer-bytelength.js
@@ -65,7 +65,7 @@ assert.strictEqual(Buffer.byteLength(float64), 64);
 const dv = new DataView(new ArrayBuffer(2));
 assert.strictEqual(Buffer.byteLength(dv), 2);
 
-// special case: zero length string
+// Special case: zero length string
 assert.strictEqual(Buffer.byteLength('', 'ascii'), 0);
 assert.strictEqual(Buffer.byteLength('', 'HeX'), 0);
 
diff --git a/test/parallel/test-buffer-copy.js b/test/parallel/test-buffer-copy.js
index ec227a93741ec2..b35609743764b3 100644
--- a/test/parallel/test-buffer-copy.js
+++ b/test/parallel/test-buffer-copy.js
@@ -70,7 +70,7 @@ let cntr = 0;
 }
 
 {
-  // copy starting near end of b to c
+  // Copy starting near end of b to c
   b.fill(++cntr);
   c.fill(++cntr);
   const copied = b.copy(c, 0, b.length - Math.floor(c.length / 2));
@@ -113,7 +113,7 @@ bb.fill('hello crazy world');
 // Try to copy from before the beginning of b. Should not throw.
 b.copy(c, 0, 100, 10);
 
-// copy throws at negative sourceStart
+// Copy throws at negative sourceStart
 common.expectsError(
   () => Buffer.allocUnsafe(5).copy(Buffer.allocUnsafe(5), 0, -1),
   errorProperty);
diff --git a/test/parallel/test-buffer-indexof.js b/test/parallel/test-buffer-indexof.js
index 0f7d7824366215..cba6af44e5b02d 100644
--- a/test/parallel/test-buffer-indexof.js
+++ b/test/parallel/test-buffer-indexof.js
@@ -78,7 +78,7 @@ assert.strictEqual(b.indexOf(Buffer.from('f'), 6), -1);
 
 assert.strictEqual(Buffer.from('ff').indexOf(Buffer.from('f'), 1, 'ucs2'), -1);
 
-// test invalid and uppercase encoding
+// Test invalid and uppercase encoding
 assert.strictEqual(b.indexOf('b', 'utf8'), 1);
 assert.strictEqual(b.indexOf('b', 'UTF8'), 1);
 assert.strictEqual(b.indexOf('62', 'HEX'), 1);
diff --git a/test/parallel/test-buffer-iterator.js b/test/parallel/test-buffer-iterator.js
index 3120ff1d2ab457..72b775c71313d7 100644
--- a/test/parallel/test-buffer-iterator.js
+++ b/test/parallel/test-buffer-iterator.js
@@ -16,7 +16,7 @@ for (b of buffer)
 assert.deepStrictEqual(arr, [1, 2, 3, 4, 5]);
 
 
-// buffer iterators should be iterable
+// Buffer iterators should be iterable
 
 arr = [];
 
diff --git a/test/parallel/test-buffer-read.js b/test/parallel/test-buffer-read.js
index 1adf0303566380..7b3b9eb8e2b1a7 100644
--- a/test/parallel/test-buffer-read.js
+++ b/test/parallel/test-buffer-read.js
@@ -2,7 +2,7 @@
 const common = require('../common');
 const assert = require('assert');
 
-// testing basic buffer read functions
+// Testing basic buffer read functions
 const buf = Buffer.from([0xa4, 0xfd, 0x48, 0xea, 0xcf, 0xff, 0xd9, 0x01, 0xde]);
 
 function read(buff, funx, args, expected) {
diff --git a/test/parallel/test-buffer-slow.js b/test/parallel/test-buffer-slow.js
index cb10a414771372..ade6ba16ffd83d 100644
--- a/test/parallel/test-buffer-slow.js
+++ b/test/parallel/test-buffer-slow.js
@@ -49,7 +49,7 @@ assert.strictEqual(SlowBuffer(NaN).length, 0);
 assert.strictEqual(SlowBuffer({}).length, 0);
 assert.strictEqual(SlowBuffer('string').length, 0);
 
-// should throw with invalid length
+// Should throw with invalid length
 const bufferMaxSizeMsg = common.expectsError({
   code: 'ERR_INVALID_OPT_VALUE',
   type: RangeError,
diff --git a/test/parallel/test-child-process-constructor.js b/test/parallel/test-child-process-constructor.js
index bf7fffd9c5456f..f0bebd61efc057 100644
--- a/test/parallel/test-child-process-constructor.js
+++ b/test/parallel/test-child-process-constructor.js
@@ -85,7 +85,7 @@ child.spawn({
 assert.strictEqual(child.hasOwnProperty('pid'), true);
 assert(Number.isInteger(child.pid));
 
-// try killing with invalid signal
+// Try killing with invalid signal
 common.expectsError(
   () => { child.kill('foo'); },
   { code: 'ERR_UNKNOWN_SIGNAL', type: TypeError }
diff --git a/test/parallel/test-child-process-disconnect.js b/test/parallel/test-child-process-disconnect.js
index 8ca39b5790e243..7ba30b28db3d3e 100644
--- a/test/parallel/test-child-process-disconnect.js
+++ b/test/parallel/test-child-process-disconnect.js
@@ -57,7 +57,7 @@ if (process.argv[2] === 'child') {
     socket.write('ready');
   });
 
-  // when the server is ready tell parent
+  // When the server is ready tell parent
   server.on('listening', function() {
     process.send({ msg: 'ready', port: server.address().port });
   });
diff --git a/test/parallel/test-child-process-double-pipe.js b/test/parallel/test-child-process-double-pipe.js
index 8503ebf69cc89d..bf640fd3798345 100644
--- a/test/parallel/test-child-process-double-pipe.js
+++ b/test/parallel/test-child-process-double-pipe.js
@@ -65,7 +65,7 @@ grep.stdin.on('drain', function(data) {
   echo.stdout.resume();
 });
 
-// propagate end from echo to grep
+// Propagate end from echo to grep
 echo.stdout.on('end', function(code) {
   grep.stdin.end();
 });
@@ -95,7 +95,7 @@ sed.stdin.on('drain', function(data) {
   grep.stdout.resume();
 });
 
-// propagate end from grep to sed
+// Propagate end from grep to sed
 grep.stdout.on('end', function(code) {
   console.error('grep stdout end');
   sed.stdin.end();
diff --git a/test/parallel/test-child-process-fork-ref.js b/test/parallel/test-child-process-fork-ref.js
index 3eae2b242e9ce2..bbf4432af80866 100644
--- a/test/parallel/test-child-process-fork-ref.js
+++ b/test/parallel/test-child-process-fork-ref.js
@@ -27,7 +27,7 @@ const fork = require('child_process').fork;
 if (process.argv[2] === 'child') {
   process.send('1');
 
-  // check that child don't instantly die
+  // Check that child don't instantly die
   setTimeout(function() {
     process.send('2');
   }, 200);
diff --git a/test/parallel/test-child-process-stdio-big-write-end.js b/test/parallel/test-child-process-stdio-big-write-end.js
index 00fc0471d235aa..07656c04ca936d 100644
--- a/test/parallel/test-child-process-stdio-big-write-end.js
+++ b/test/parallel/test-child-process-stdio-big-write-end.js
@@ -56,14 +56,14 @@ function parent() {
     sent += bufsize;
   } while (child.stdin.write(buf));
 
-  // then write a bunch more times.
+  // Then write a bunch more times.
   for (let i = 0; i < 100; i++) {
     const buf = Buffer.alloc(bufsize, '.');
     sent += bufsize;
     child.stdin.write(buf);
   }
 
-  // now end, before it's all flushed.
+  // Now end, before it's all flushed.
   child.stdin.end();
 
   // now we wait...
diff --git a/test/parallel/test-child-process-stdio-inherit.js b/test/parallel/test-child-process-stdio-inherit.js
index b77391d87dca2c..dfffb70c582016 100644
--- a/test/parallel/test-child-process-stdio-inherit.js
+++ b/test/parallel/test-child-process-stdio-inherit.js
@@ -45,7 +45,7 @@ function grandparent() {
   child.on('close', function(code, signal) {
     assert.strictEqual(code, 0);
     assert.strictEqual(signal, null);
-    // cat on windows adds a \r\n at the end.
+    // 'cat' on windows adds a \r\n at the end.
     assert.strictEqual(output.trim(), input.trim());
   });
 }
diff --git a/test/parallel/test-child-process-validate-stdio.js b/test/parallel/test-child-process-validate-stdio.js
index 71edc0559755b2..3566c8f9520f30 100644
--- a/test/parallel/test-child-process-validate-stdio.js
+++ b/test/parallel/test-child-process-validate-stdio.js
@@ -11,7 +11,7 @@ const expectedError =
 // Should throw if string and not ignore, pipe, or inherit
 assert.throws(() => _validateStdio('foo'), expectedError);
 
-// should throw if not a string or array
+// Should throw if not a string or array
 assert.throws(() => _validateStdio(600), expectedError);
 
 // Should populate stdio with undefined if len < 3
diff --git a/test/parallel/test-cli-syntax-piped-bad.js b/test/parallel/test-cli-syntax-piped-bad.js
index 864497e8f75c94..4fb24b24f339c7 100644
--- a/test/parallel/test-cli-syntax-piped-bad.js
+++ b/test/parallel/test-cli-syntax-piped-bad.js
@@ -25,7 +25,7 @@ syntaxArgs.forEach(function(args) {
   // stderr should include '[stdin]' as the filename
   assert(c.stderr.startsWith('[stdin]'), `${c.stderr} starts with ${stdin}`);
 
-  // no stdout or stderr should be produced
+  // No stdout or stderr should be produced
   assert.strictEqual(c.stdout, '');
 
   // stderr should have a syntax error message
diff --git a/test/parallel/test-cli-syntax-piped-good.js b/test/parallel/test-cli-syntax-piped-good.js
index b3467b037212ab..cdadf449d87b41 100644
--- a/test/parallel/test-cli-syntax-piped-good.js
+++ b/test/parallel/test-cli-syntax-piped-good.js
@@ -18,7 +18,7 @@ syntaxArgs.forEach(function(args) {
   const stdin = 'throw new Error("should not get run");';
   const c = spawnSync(node, args, { encoding: 'utf8', input: stdin });
 
-  // no stdout or stderr should be produced
+  // No stdout or stderr should be produced
   assert.strictEqual(c.stdout, '');
   assert.strictEqual(c.stderr, '');
 
diff --git a/test/parallel/test-cluster-disconnect.js b/test/parallel/test-cluster-disconnect.js
index 36def06a4c3dd2..51cbb43c63f5a4 100644
--- a/test/parallel/test-cluster-disconnect.js
+++ b/test/parallel/test-cluster-disconnect.js
@@ -92,7 +92,7 @@ if (cluster.isWorker) {
       testCluster(common.mustCall(() => {
         // 3. disconnect cluster
         cluster.disconnect(common.mustCall(() => {
-          // run test again to confirm cleanup
+          // Run test again to confirm cleanup
           if (again) {
             test();
           }
diff --git a/test/parallel/test-cluster-eaccess.js b/test/parallel/test-cluster-eaccess.js
index 7a3bc1c5cd1311..4c2d28429307dc 100644
--- a/test/parallel/test-cluster-eaccess.js
+++ b/test/parallel/test-cluster-eaccess.js
@@ -41,7 +41,7 @@ if (cluster.isMaster && process.argv.length !== 3) {
   // Makes sure master is able to fork the worker
   cluster.on('fork', common.mustCall());
 
-  // makes sure the worker is ready
+  // Makes sure the worker is ready
   worker.on('online', common.mustCall());
 
   worker.on('message', common.mustCall(function(err) {
@@ -71,7 +71,7 @@ if (cluster.isMaster && process.argv.length !== 3) {
     });
   }));
 } else if (process.argv.length === 3) {
-  // child process (of cluster.worker)
+  // Child process (of cluster.worker)
   const PIPE_NAME = process.argv[2];
 
   const server = net.createServer().listen(PIPE_NAME, common.mustCall(() => {
diff --git a/test/parallel/test-cluster-listening-port.js b/test/parallel/test-cluster-listening-port.js
index 84bf49fa96c81f..40d66065d947ce 100644
--- a/test/parallel/test-cluster-listening-port.js
+++ b/test/parallel/test-cluster-listening-port.js
@@ -8,9 +8,9 @@ if (cluster.isMaster) {
   cluster.fork();
   cluster.on('listening', common.mustCall(function(worker, address) {
     const port = address.port;
-    // ensure that the port is not 0 or null
+    // Ensure that the port is not 0 or null
     assert(port);
-    // ensure that the port is numerical
+    // Ensure that the port is numerical
     assert.strictEqual(typeof port, 'number');
     worker.kill();
   }));
diff --git a/test/parallel/test-cluster-net-listen.js b/test/parallel/test-cluster-net-listen.js
index f6b2c4e45a6eb9..ff102797eab8f9 100644
--- a/test/parallel/test-cluster-net-listen.js
+++ b/test/parallel/test-cluster-net-listen.js
@@ -26,7 +26,7 @@ const cluster = require('cluster');
 const net = require('net');
 
 if (cluster.isMaster) {
-  // ensure that the worker exits peacefully
+  // Ensure that the worker exits peacefully
   cluster.fork().on('exit', common.mustCall(function(statusCode) {
     assert.strictEqual(statusCode, 0);
   }));
diff --git a/test/parallel/test-common.js b/test/parallel/test-common.js
index a133204437facb..62f4eb050fb5d5 100644
--- a/test/parallel/test-common.js
+++ b/test/parallel/test-common.js
@@ -26,7 +26,7 @@ const fixtures = require('../common/fixtures');
 const assert = require('assert');
 const { execFile } = require('child_process');
 
-// test for leaked global detection
+// Test for leaked global detection
 {
   const p = fixtures.path('leakedGlobal.js');
   execFile(process.execPath, [p], common.mustCall((err, stdout, stderr) => {
diff --git a/test/parallel/test-console.js b/test/parallel/test-console.js
index 4a7a2fda683ef6..87ee8ad1ff1230 100644
--- a/test/parallel/test-console.js
+++ b/test/parallel/test-console.js
@@ -93,35 +93,35 @@ hijackStderr(function(data) {
   errStrings.push(data);
 });
 
-// test console.log() goes to stdout
+// Test console.log() goes to stdout
 console.log('foo');
 console.log('foo', 'bar');
 console.log('%s %s', 'foo', 'bar', 'hop');
 console.log({ slashes: '\\\\' });
 console.log(custom_inspect);
 
-// test console.debug() goes to stdout
+// Test console.debug() goes to stdout
 console.debug('foo');
 console.debug('foo', 'bar');
 console.debug('%s %s', 'foo', 'bar', 'hop');
 console.debug({ slashes: '\\\\' });
 console.debug(custom_inspect);
 
-// test console.info() goes to stdout
+// Test console.info() goes to stdout
 console.info('foo');
 console.info('foo', 'bar');
 console.info('%s %s', 'foo', 'bar', 'hop');
 console.info({ slashes: '\\\\' });
 console.info(custom_inspect);
 
-// test console.error() goes to stderr
+// Test console.error() goes to stderr
 console.error('foo');
 console.error('foo', 'bar');
 console.error('%s %s', 'foo', 'bar', 'hop');
 console.error({ slashes: '\\\\' });
 console.error(custom_inspect);
 
-// test console.warn() goes to stderr
+// Test console.warn() goes to stderr
 console.warn('foo');
 console.warn('foo', 'bar');
 console.warn('%s %s', 'foo', 'bar', 'hop');
diff --git a/test/parallel/test-crypto-binary-default.js b/test/parallel/test-crypto-binary-default.js
index bb0247bf5817b5..80be4dea11e63b 100644
--- a/test/parallel/test-crypto-binary-default.js
+++ b/test/parallel/test-crypto-binary-default.js
@@ -480,8 +480,8 @@ function testCipher1(key) {
 
 
 function testCipher2(key) {
-  // encryption and decryption with Base64
-  // reported in https://github.com/joyent/node/issues/738
+  // Encryption and decryption with Base64.
+  // Reported in https://github.com/joyent/node/issues/738
   const plaintext =
       '32|RmVZZkFUVmpRRkp0TmJaUm56ZU9qcnJkaXNNWVNpTTU*|iXmckfRWZBGWWELw' +
       'eCBsThSsfUHLeRe0KCsK8ooHgxie0zOINpXxfZi/oNG7uq9JWFVCk70gfzQH8ZUJ' +
diff --git a/test/parallel/test-crypto-cipher-decipher.js b/test/parallel/test-crypto-cipher-decipher.js
index 9f79abc70545dd..e7ab8f73b02b0b 100644
--- a/test/parallel/test-crypto-cipher-decipher.js
+++ b/test/parallel/test-crypto-cipher-decipher.js
@@ -53,16 +53,16 @@ function testCipher1(key) {
 
 
 function testCipher2(key) {
-  // encryption and decryption with Base64
-  // reported in https://github.com/joyent/node/issues/738
+  // Encryption and decryption with Base64.
+  // Reported in https://github.com/joyent/node/issues/738
   const plaintext =
       '32|RmVZZkFUVmpRRkp0TmJaUm56ZU9qcnJkaXNNWVNpTTU*|iXmckfRWZBGWWELw' +
       'eCBsThSsfUHLeRe0KCsK8ooHgxie0zOINpXxfZi/oNG7uq9JWFVCk70gfzQH8ZUJ' +
       'jAfaFg**';
   const cipher = crypto.createCipher('aes256', key);
 
-  // Encrypt plaintext which is in utf8 format
-  // to a ciphertext which will be in Base64
+  // Encrypt plaintext which is in utf8 format to a ciphertext which will be in
+  // Base64.
   let ciph = cipher.update(plaintext, 'utf8', 'base64');
   ciph += cipher.final('base64');
 
diff --git a/test/parallel/test-crypto-from-binary.js b/test/parallel/test-crypto-from-binary.js
index 56d0cb72079f82..3b3c6a81ef6a4a 100644
--- a/test/parallel/test-crypto-from-binary.js
+++ b/test/parallel/test-crypto-from-binary.js
@@ -36,7 +36,7 @@ const EXTERN_APEX = 0xFBEE9;
 // Manually controlled string for checking binary output
 let ucs2_control = 'a\u0000';
 
-// grow the strings to proper length
+// Grow the strings to proper length
 while (ucs2_control.length <= EXTERN_APEX) {
   ucs2_control = ucs2_control.repeat(2);
 }
diff --git a/test/parallel/test-crypto-keygen.js b/test/parallel/test-crypto-keygen.js
index 7b3eee570ddf40..43f2196115816e 100644
--- a/test/parallel/test-crypto-keygen.js
+++ b/test/parallel/test-crypto-keygen.js
@@ -635,7 +635,7 @@ const sec1EncExp = (cipher) => getRegExpForPEM('EC PRIVATE KEY', cipher);
     message: 'Unknown cipher'
   });
 
-  // cipher, but no valid passphrase.
+  // Cipher, but no valid passphrase.
   for (const passphrase of [undefined, null, 5, false, true]) {
     common.expectsError(() => generateKeyPairSync('rsa', {
       modulusLength: 4096,
diff --git a/test/parallel/test-domain-multi.js b/test/parallel/test-domain-multi.js
index 45d94b35a17c4c..63701150f8c331 100644
--- a/test/parallel/test-domain-multi.js
+++ b/test/parallel/test-domain-multi.js
@@ -27,7 +27,7 @@ const domain = require('domain');
 const http = require('http');
 
 const a = domain.create();
-a.enter(); // this will be our "root" domain
+a.enter(); // This will be our "root" domain
 
 a.on('error', common.mustNotCall());
 
@@ -62,11 +62,11 @@ const server = http.createServer((req, res) => {
   const c = domain.create();
   const req = http.get({ host: 'localhost', port: server.address().port });
 
-  // add the request to the C domain
+  // Add the request to the C domain
   c.add(req);
 
   req.on('response', (res) => {
-    // add the response object to the C domain
+    // Add the response object to the C domain
     c.add(res);
     res.pipe(process.stdout);
   });
diff --git a/test/parallel/test-event-emitter-add-listeners.js b/test/parallel/test-event-emitter-add-listeners.js
index 6ef39522183d4f..7812de670ff5fb 100644
--- a/test/parallel/test-event-emitter-add-listeners.js
+++ b/test/parallel/test-event-emitter-add-listeners.js
@@ -60,7 +60,7 @@ const EventEmitter = require('events');
   ee.emit('hello', 'a', 'b');
 }
 
-// just make sure that this doesn't throw:
+// Just make sure that this doesn't throw:
 {
   const f = new EventEmitter();
 
diff --git a/test/parallel/test-file-write-stream2.js b/test/parallel/test-file-write-stream2.js
index e29bd80ebf792c..5e18ad44ae7dfa 100644
--- a/test/parallel/test-file-write-stream2.js
+++ b/test/parallel/test-file-write-stream2.js
@@ -62,7 +62,7 @@ function removeTestFile() {
 
 tmpdir.refresh();
 
-// drain at 0, return false at 10.
+// Drain at 0, return false at 10.
 const file = fs.createWriteStream(filepath, {
   highWaterMark: 11
 });
diff --git a/test/parallel/test-fs-append-file-sync.js b/test/parallel/test-fs-append-file-sync.js
index e053d061610b11..190381234aa5ad 100644
--- a/test/parallel/test-fs-append-file-sync.js
+++ b/test/parallel/test-fs-append-file-sync.js
@@ -39,7 +39,7 @@ const data = '南越国是前203年至前111年存在于岭南地区的一个国
 const tmpdir = require('../common/tmpdir');
 tmpdir.refresh();
 
-// Test that empty file will be created and have content added
+// Test that empty file will be created and have content added.
 const filename = join(tmpdir.path, 'append-sync.txt');
 
 fs.appendFileSync(filename, data);
@@ -48,7 +48,7 @@ const fileData = fs.readFileSync(filename);
 
 assert.strictEqual(Buffer.byteLength(data), fileData.length);
 
-// Test that appends data to a non empty file
+// Test that appends data to a non empty file.
 const filename2 = join(tmpdir.path, 'append-sync2.txt');
 fs.writeFileSync(filename2, currentFileData);
 
@@ -59,7 +59,7 @@ const fileData2 = fs.readFileSync(filename2);
 assert.strictEqual(Buffer.byteLength(data) + currentFileData.length,
                    fileData2.length);
 
-// Test that appendFileSync accepts buffers
+// Test that appendFileSync accepts buffers.
 const filename3 = join(tmpdir.path, 'append-sync3.txt');
 fs.writeFileSync(filename3, currentFileData);
 
@@ -70,13 +70,13 @@ const fileData3 = fs.readFileSync(filename3);
 
 assert.strictEqual(buf.length + currentFileData.length, fileData3.length);
 
-// test that appendFile accepts numbers.
+// Test that appendFile accepts numbers.
 const filename4 = join(tmpdir.path, 'append-sync4.txt');
 fs.writeFileSync(filename4, currentFileData, { mode: m });
 
 fs.appendFileSync(filename4, num, { mode: m });
 
-// windows permissions aren't unix
+// Windows permissions aren't Unix.
 if (!common.isWindows) {
   const st = fs.statSync(filename4);
   assert.strictEqual(st.mode & 0o700, m);
@@ -87,7 +87,7 @@ const fileData4 = fs.readFileSync(filename4);
 assert.strictEqual(Buffer.byteLength(String(num)) + currentFileData.length,
                    fileData4.length);
 
-// Test that appendFile accepts file descriptors
+// Test that appendFile accepts file descriptors.
 const filename5 = join(tmpdir.path, 'append-sync5.txt');
 fs.writeFileSync(filename5, currentFileData);
 
@@ -100,7 +100,7 @@ const fileData5 = fs.readFileSync(filename5);
 assert.strictEqual(Buffer.byteLength(data) + currentFileData.length,
                    fileData5.length);
 
-// Exit logic for cleanup
+// Exit logic for cleanup.
 
 process.on('exit', function() {
   fs.unlinkSync(filename);
diff --git a/test/parallel/test-fs-append-file.js b/test/parallel/test-fs-append-file.js
index 3122982e2a4af4..90fe8d9277a23e 100644
--- a/test/parallel/test-fs-append-file.js
+++ b/test/parallel/test-fs-append-file.js
@@ -42,7 +42,7 @@ tmpdir.refresh();
 
 const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
 
-// Test that empty file will be created and have content added (callback API)
+// Test that empty file will be created and have content added (callback API).
 {
   const filename = join(tmpdir.path, 'append.txt');
 
@@ -56,7 +56,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   }));
 }
 
-// Test that empty file will be created and have content added (promise API)
+// Test that empty file will be created and have content added (promise API).
 {
   const filename = join(tmpdir.path, 'append-promise.txt');
 
@@ -68,7 +68,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
     .catch(throwNextTick);
 }
 
-// Test that appends data to a non-empty file (callback API)
+// Test that appends data to a non-empty file (callback API).
 {
   const filename = join(tmpdir.path, 'append-non-empty.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -84,7 +84,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   }));
 }
 
-// Test that appends data to a non-empty file (promise API)
+// Test that appends data to a non-empty file (promise API).
 {
   const filename = join(tmpdir.path, 'append-non-empty-promise.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -98,7 +98,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
     .catch(throwNextTick);
 }
 
-// Test that appendFile accepts buffers (callback API)
+// Test that appendFile accepts buffers (callback API).
 {
   const filename = join(tmpdir.path, 'append-buffer.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -115,7 +115,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   }));
 }
 
-// Test that appendFile accepts buffers (promises API)
+// Test that appendFile accepts buffers (promises API).
 {
   const filename = join(tmpdir.path, 'append-buffer-promises.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -130,7 +130,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
     .catch(throwNextTick);
 }
 
-// Test that appendFile accepts numbers (callback API)
+// Test that appendFile accepts numbers (callback API).
 {
   const filename = join(tmpdir.path, 'append-numbers.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -139,7 +139,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   fs.appendFile(filename, n, { mode: m }, common.mustCall((e) => {
     assert.ifError(e);
 
-    // windows permissions aren't unix
+    // Windows permissions aren't Unix.
     if (!common.isWindows) {
       const st = fs.statSync(filename);
       assert.strictEqual(st.mode & 0o700, m);
@@ -153,7 +153,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   }));
 }
 
-// Test that appendFile accepts numbers (promises API)
+// Test that appendFile accepts numbers (promises API).
 {
   const filename = join(tmpdir.path, 'append-numbers-promises.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -161,7 +161,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   const m = 0o600;
   fs.promises.appendFile(filename, n, { mode: m })
     .then(common.mustCall(() => {
-      // windows permissions aren't unix
+      // Windows permissions aren't Unix.
       if (!common.isWindows) {
         const st = fs.statSync(filename);
         assert.strictEqual(st.mode & 0o700, m);
@@ -176,7 +176,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
     .catch(throwNextTick);
 }
 
-// Test that appendFile accepts file descriptors (callback API)
+// Test that appendFile accepts file descriptors (callback API).
 {
   const filename = join(tmpdir.path, 'append-descriptors.txt');
   fs.writeFileSync(filename, currentFileData);
@@ -200,7 +200,7 @@ const throwNextTick = (e) => { process.nextTick(() => { throw e; }); };
   }));
 }
 
-// Test that appendFile accepts file descriptors (promises API)
+// Test that appendFile accepts file descriptors (promises API).
 {
   const filename = join(tmpdir.path, 'append-descriptors-promises.txt');
   fs.writeFileSync(filename, currentFileData);
diff --git a/test/parallel/test-fs-error-messages.js b/test/parallel/test-fs-error-messages.js
index dd5438c44bfce9..370b4f46977a20 100644
--- a/test/parallel/test-fs-error-messages.js
+++ b/test/parallel/test-fs-error-messages.js
@@ -321,7 +321,7 @@ function re(literals, ...values) {
         `ENOTEMPTY: directory not empty, rename '${existingDir}' -> ` +
         `'${existingDir2}'`);
       assert.strictEqual(err.errno, UV_ENOTEMPTY);
-    } else if (err.code === 'EXDEV') {  // not on the same mounted filesystem
+    } else if (err.code === 'EXDEV') {  // Not on the same mounted filesystem
       assert.strictEqual(
         err.message,
         `EXDEV: cross-device link not permitted, rename '${existingDir}' -> ` +
diff --git a/test/parallel/test-fs-link.js b/test/parallel/test-fs-link.js
index 9b95fc3e026140..f4f3f787d7fd51 100644
--- a/test/parallel/test-fs-link.js
+++ b/test/parallel/test-fs-link.js
@@ -7,7 +7,7 @@ const fs = require('fs');
 const tmpdir = require('../common/tmpdir');
 tmpdir.refresh();
 
-// test creating and reading hard link
+// Test creating and reading hard link
 const srcPath = path.join(tmpdir.path, 'hardlink-target.txt');
 const dstPath = path.join(tmpdir.path, 'link1.js');
 fs.writeFileSync(srcPath, 'hello world');
diff --git a/test/parallel/test-fs-mkdir.js b/test/parallel/test-fs-mkdir.js
index f2ed9b9f68ed92..2a15627a0f1767 100644
--- a/test/parallel/test-fs-mkdir.js
+++ b/test/parallel/test-fs-mkdir.js
@@ -132,7 +132,7 @@ function nextdir() {
   }
 }
 
-// mkdirp when folder does not yet exist.
+// `mkdirp` when folder does not yet exist.
 {
   const pathname = path.join(tmpdir.path, nextdir(), nextdir());
 
diff --git a/test/parallel/test-fs-open.js b/test/parallel/test-fs-open.js
index 788124825249ca..9a1ae623fea302 100644
--- a/test/parallel/test-fs-open.js
+++ b/test/parallel/test-fs-open.js
@@ -27,7 +27,7 @@ const fs = require('fs');
 let caughtException = false;
 
 try {
-  // should throw ENOENT, not EBADF
+  // Should throw ENOENT, not EBADF
   // see https://github.com/joyent/node/pull/1228
   fs.openSync('/path/to/file/that/does/not/exist', 'r');
 } catch (e) {
diff --git a/test/parallel/test-fs-promises-file-handle-chmod.js b/test/parallel/test-fs-promises-file-handle-chmod.js
index cb7a1c6317be41..2a05218969ee0a 100644
--- a/test/parallel/test-fs-promises-file-handle-chmod.js
+++ b/test/parallel/test-fs-promises-file-handle-chmod.js
@@ -17,7 +17,7 @@ tmpdir.refresh();
 async function validateFilePermission() {
   const filePath = path.resolve(tmpDir, 'tmp-chmod.txt');
   const fileHandle = await open(filePath, 'w+', 0o444);
-  // file created with r--r--r-- 444
+  // File created with r--r--r-- 444
   const statsBeforeMod = fs.statSync(filePath);
   assert.deepStrictEqual(statsBeforeMod.mode & 0o444, 0o444);
 
@@ -34,7 +34,7 @@ async function validateFilePermission() {
     expectedAccess = newPermissions;
   }
 
-  // change the permissions to rwxr--r-x
+  // Change the permissions to rwxr--r-x
   await fileHandle.chmod(newPermissions);
   const statsAfterMod = fs.statSync(filePath);
   assert.deepStrictEqual(statsAfterMod.mode & expectedAccess, expectedAccess);
diff --git a/test/parallel/test-fs-promises.js b/test/parallel/test-fs-promises.js
index 749e0a6f087107..97b5f8326e6052 100644
--- a/test/parallel/test-fs-promises.js
+++ b/test/parallel/test-fs-promises.js
@@ -119,7 +119,7 @@ async function getHandle(dest) {
       await unlink(dest);
     }
 
-    // bytes written to file match buffer
+    // Bytes written to file match buffer
     {
       const handle = await getHandle(dest);
       const buf = Buffer.from('hello fsPromises');
@@ -130,7 +130,7 @@ async function getHandle(dest) {
       assert.deepStrictEqual(ret.buffer, buf);
     }
 
-    // truncate file to specified length
+    // Truncate file to specified length
     {
       const handle = await getHandle(dest);
       const buf = Buffer.from('hello FileHandle');
@@ -224,7 +224,7 @@ async function getHandle(dest) {
 
         const newMode = 0o666;
         if (common.isOSX) {
-          // lchmod is only available on macOS
+          // `lchmod` is only available on macOS.
           await lchmod(newLink, newMode);
           stats = await lstat(newLink);
           assert.strictEqual(stats.mode & 0o777, newMode);
@@ -287,7 +287,7 @@ async function getHandle(dest) {
       assert(stats.isDirectory());
     }
 
-    // mkdirp when folder does not yet exist.
+    // `mkdirp` when folder does not yet exist.
     {
       const dir = path.join(tmpDir, nextdir(), nextdir());
       await mkdir(dir, { recursive: true });
@@ -344,7 +344,7 @@ async function getHandle(dest) {
       });
     }
 
-    // mkdtemp with invalid numeric prefix
+    // `mkdtemp` with invalid numeric prefix
     {
       await mkdtemp(path.resolve(tmpDir, 'FOO'));
       assert.rejects(
diff --git a/test/parallel/test-fs-read-stream-err.js b/test/parallel/test-fs-read-stream-err.js
index a9b4838cf1834f..1d280f64874fc7 100644
--- a/test/parallel/test-fs-read-stream-err.js
+++ b/test/parallel/test-fs-read-stream-err.js
@@ -43,15 +43,15 @@ fs.close = common.mustCall((fd_, cb) => {
 
 const read = fs.read;
 fs.read = function() {
-  // first time is ok.
+  // First time is ok.
   read.apply(fs, arguments);
-  // then it breaks
+  // Then it breaks.
   fs.read = common.mustCall(function() {
     const cb = arguments[arguments.length - 1];
     process.nextTick(() => {
       cb(err);
     });
-    // and should not be called again!
+    // It should not be called again!
     fs.read = () => {
       throw new Error('BOOM!');
     };
diff --git a/test/parallel/test-fs-read-stream-inherit.js b/test/parallel/test-fs-read-stream-inherit.js
index a081302cc5a0f1..69f3b9c3f724bd 100644
--- a/test/parallel/test-fs-read-stream-inherit.js
+++ b/test/parallel/test-fs-read-stream-inherit.js
@@ -140,7 +140,7 @@ const rangeFile = fixtures.path('x.txt');
   }));
 }
 
-// pause and then resume immediately.
+// Pause and then resume immediately.
 {
   const pauseRes = fs.createReadStream(rangeFile);
   pauseRes.pause();
diff --git a/test/parallel/test-fs-read-stream.js b/test/parallel/test-fs-read-stream.js
index 2a07a09c976574..b1559ed9ea8c04 100644
--- a/test/parallel/test-fs-read-stream.js
+++ b/test/parallel/test-fs-read-stream.js
@@ -206,7 +206,7 @@ if (!common.isWindows) {
 }
 
 {
-  // pause and then resume immediately.
+  // Pause and then resume immediately.
   const pauseRes = fs.createReadStream(rangeFile);
   pauseRes.pause();
   pauseRes.resume();
diff --git a/test/parallel/test-fs-realpath.js b/test/parallel/test-fs-realpath.js
index 1eaf1681d75fba..48294d4a62e0ec 100644
--- a/test/parallel/test-fs-realpath.js
+++ b/test/parallel/test-fs-realpath.js
@@ -365,7 +365,7 @@ function test_upone_actual(realpath, realpathSync, cb) {
   cb();
 }
 
-// going up with .. multiple times
+// Going up with .. multiple times
 // .
 // `-- a/
 //     |-- b/
@@ -407,7 +407,7 @@ function test_up_multiple(realpath, realpathSync, cb) {
 }
 
 
-// absolute symlinks with children.
+// Absolute symlinks with children.
 // .
 // `-- a/
 //     |-- b/
diff --git a/test/parallel/test-fs-symlink-dir-junction.js b/test/parallel/test-fs-symlink-dir-junction.js
index 5bd7a8dcc4ecc3..fc89ad368401e4 100644
--- a/test/parallel/test-fs-symlink-dir-junction.js
+++ b/test/parallel/test-fs-symlink-dir-junction.js
@@ -28,7 +28,7 @@ const fs = require('fs');
 
 const tmpdir = require('../common/tmpdir');
 
-// test creating and reading symbolic link
+// Test creating and reading symbolic link
 const linkData = fixtures.path('cycles/');
 const linkPath = path.join(tmpdir.path, 'cycles_link');
 
diff --git a/test/parallel/test-fs-utimes.js b/test/parallel/test-fs-utimes.js
index 93932e27d7e777..e34953423bd11f 100644
--- a/test/parallel/test-fs-utimes.js
+++ b/test/parallel/test-fs-utimes.js
@@ -33,7 +33,7 @@ function stat_resource(resource) {
     return fs.statSync(resource);
   } else {
     const stats = fs.fstatSync(resource);
-    // ensure mtime has been written to disk
+    // Ensure mtime has been written to disk
     // except for directories on AIX where it cannot be synced
     if (common.isAIX && stats.isDirectory())
       return stats;
@@ -59,8 +59,8 @@ function expect_errno(syscall, resource, err, errno) {
 function expect_ok(syscall, resource, err, atime, mtime) {
   const mtime_diff = check_mtime(resource, mtime);
   assert(
-    // check up to single-second precision
-    // sub-second precision is OS and fs dependant
+    // Check up to single-second precision.
+    // Sub-second precision is OS and fs dependant.
     !err && (mtime_diff < 2) || err && err.code === 'ENOSYS',
     `FAILED: expect_ok ${util.inspect(arguments)}
      check_mtime: ${mtime_diff}`
@@ -82,7 +82,7 @@ runTests(cases.values());
 function runTests(iter) {
   const { value, done } = iter.next();
   if (done) return;
-  // Support easy setting same or different atime / mtime values
+  // Support easy setting same or different atime / mtime values.
   const [atime, mtime] = Array.isArray(value) ? value : [value, value];
 
   let fd;
@@ -119,7 +119,7 @@ function runTests(iter) {
     fs.utimesSync(tmpdir.path, atime, mtime);
     expect_ok('utimesSync', tmpdir.path, undefined, atime, mtime);
 
-    // some systems don't have futimes
+    // Some systems don't have futimes
     // if there's an error, it should be ENOSYS
     try {
       fs.futimesSync(fd, atime, mtime);
diff --git a/test/parallel/test-fs-write-file.js b/test/parallel/test-fs-write-file.js
index 7f0ec116f1c632..b9536bea4ca131 100644
--- a/test/parallel/test-fs-write-file.js
+++ b/test/parallel/test-fs-write-file.js
@@ -48,7 +48,7 @@ fs.writeFile(filename, s, common.mustCall(function(e) {
   }));
 }));
 
-// test that writeFile accepts buffers
+// Test that writeFile accepts buffers.
 const filename2 = join(tmpdir.path, 'test2.txt');
 const buf = Buffer.from(s, 'utf8');
 
@@ -62,14 +62,14 @@ fs.writeFile(filename2, buf, common.mustCall(function(e) {
   }));
 }));
 
-// test that writeFile accepts numbers.
+// Test that writeFile accepts numbers.
 const filename3 = join(tmpdir.path, 'test3.txt');
 
 const m = 0o600;
 fs.writeFile(filename3, n, { mode: m }, common.mustCall(function(e) {
   assert.ifError(e);
 
-  // windows permissions aren't unix
+  // Windows permissions aren't Unix.
   if (!common.isWindows) {
     const st = fs.statSync(filename3);
     assert.strictEqual(st.mode & 0o700, m);
@@ -82,7 +82,7 @@ fs.writeFile(filename3, n, { mode: m }, common.mustCall(function(e) {
   }));
 }));
 
-// Test that writeFile accepts file descriptors
+// Test that writeFile accepts file descriptors.
 const filename4 = join(tmpdir.path, 'test4.txt');
 
 fs.open(filename4, 'w+', common.mustCall(function(e, fd) {
diff --git a/test/parallel/test-fs-write-stream-err.js b/test/parallel/test-fs-write-stream-err.js
index 36bf9dbcfb068e..0db517da2a58d9 100644
--- a/test/parallel/test-fs-write-stream-err.js
+++ b/test/parallel/test-fs-write-stream-err.js
@@ -38,17 +38,17 @@ fs.write = function() {
   switch (writeCalls++) {
     case 0:
       console.error('first write');
-      // first time is ok.
+      // First time is ok.
       return write.apply(fs, arguments);
     case 1:
-      // then it breaks
+      // Then it breaks.
       console.error('second write');
       const cb = arguments[arguments.length - 1];
       return process.nextTick(function() {
         cb(err);
       });
     default:
-      // and should not be called again!
+      // It should not be called again!
       throw new Error('BOOM!');
   }
 };
diff --git a/test/parallel/test-http-agent-destroyed-socket.js b/test/parallel/test-http-agent-destroyed-socket.js
index 145dc484248ef0..5b58ef0f52a50b 100644
--- a/test/parallel/test-http-agent-destroyed-socket.js
+++ b/test/parallel/test-http-agent-destroyed-socket.js
@@ -41,7 +41,7 @@ const server = http.createServer(common.mustCall((req, res) => {
   };
 
   const request1 = http.get(requestOptions, common.mustCall((response) => {
-    // assert request2 is queued in the agent
+    // Assert request2 is queued in the agent
     const key = agent.getName(requestOptions);
     assert.strictEqual(agent.requests[key].length, 1);
     response.resume();
diff --git a/test/parallel/test-http-agent-keepalive.js b/test/parallel/test-http-agent-keepalive.js
index 4d682a89ab7a54..7e2cef4e3e7ee6 100644
--- a/test/parallel/test-http-agent-keepalive.js
+++ b/test/parallel/test-http-agent-keepalive.js
@@ -62,7 +62,7 @@ function checkDataAndSockets(body) {
 }
 
 function second() {
-  // request second, use the same socket
+  // Request second, use the same socket
   get('/second', common.mustCall((res) => {
     assert.strictEqual(res.statusCode, 200);
     res.on('data', checkDataAndSockets);
@@ -79,7 +79,7 @@ function second() {
 }
 
 function remoteClose() {
-  // mock remote server close the socket
+  // Mock remote server close the socket
   get('/remote_close', common.mustCall((res) => {
     assert.deepStrictEqual(res.statusCode, 200);
     res.on('data', checkDataAndSockets);
@@ -89,7 +89,7 @@ function remoteClose() {
       process.nextTick(common.mustCall(() => {
         assert.strictEqual(agent.sockets[name], undefined);
         assert.strictEqual(agent.freeSockets[name].length, 1);
-        // waiting remote server close the socket
+        // Waiting remote server close the socket
         setTimeout(common.mustCall(() => {
           assert.strictEqual(agent.sockets[name], undefined);
           assert.strictEqual(agent.freeSockets[name], undefined);
@@ -101,7 +101,7 @@ function remoteClose() {
 }
 
 function remoteError() {
-  // remote server will destroy the socket
+  // Remote server will destroy the socket
   const req = get('/error', common.mustNotCall());
   req.on('error', common.mustCall((err) => {
     assert(err);
diff --git a/test/parallel/test-http-client-response-domain.js b/test/parallel/test-http-client-response-domain.js
index 617dc729acb71f..ace9efc7527087 100644
--- a/test/parallel/test-http-client-response-domain.js
+++ b/test/parallel/test-http-client-response-domain.js
@@ -30,7 +30,7 @@ let d;
 const tmpdir = require('../common/tmpdir');
 tmpdir.refresh();
 
-// first fire up a simple HTTP server
+// First fire up a simple HTTP server
 const server = http.createServer(function(req, res) {
   res.writeHead(200);
   res.end();
diff --git a/test/parallel/test-http-client-spurious-aborted.js b/test/parallel/test-http-client-spurious-aborted.js
index 8f05f0cb36a2a6..296b4bd256c929 100644
--- a/test/parallel/test-http-client-spurious-aborted.js
+++ b/test/parallel/test-http-client-spurious-aborted.js
@@ -67,7 +67,7 @@ function download() {
       assert.strictEqual(aborted, abortRequest);
       finishCountdown.dec();
       if (finishCountdown.remaining === 0) return;
-      abortRequest = false; // next one should be a good response
+      abortRequest = false; // Next one should be a good response
       download();
     });
   });
diff --git a/test/parallel/test-http-client-timeout-event.js b/test/parallel/test-http-client-timeout-event.js
index c76d56ef256407..71767bef8f1641 100644
--- a/test/parallel/test-http-client-timeout-event.js
+++ b/test/parallel/test-http-client-timeout-event.js
@@ -36,7 +36,7 @@ server.listen(0, options.host, function() {
   options.port = this.address().port;
   const req = http.request(options);
   req.on('error', function() {
-    // this space is intentionally left blank
+    // This space is intentionally left blank
   });
   req.on('close', common.mustCall(() => server.close()));
 
diff --git a/test/parallel/test-http-client-timeout-option.js b/test/parallel/test-http-client-timeout-option.js
index 6741fbe0bd1e35..70837d829e01f4 100644
--- a/test/parallel/test-http-client-timeout-option.js
+++ b/test/parallel/test-http-client-timeout-option.js
@@ -17,7 +17,7 @@ server.listen(0, options.host, function() {
   options.port = this.address().port;
   const req = http.request(options);
   req.on('error', function() {
-    // this space is intentionally left blank
+    // This space is intentionally left blank
   });
   req.on('close', common.mustCall(() => server.close()));
 
diff --git a/test/parallel/test-http-client-timeout-with-data.js b/test/parallel/test-http-client-timeout-with-data.js
index bc5670b6939e39..a3f7fdd9297356 100644
--- a/test/parallel/test-http-client-timeout-with-data.js
+++ b/test/parallel/test-http-client-timeout-with-data.js
@@ -46,7 +46,7 @@ server.listen(0, options.host, function() {
 
   function onresponse(res) {
     req.setTimeout(50, common.mustCall(function() {
-      assert.strictEqual(nchunks, 1); // should have received the first chunk
+      assert.strictEqual(nchunks, 1); // Should have received the first chunk
       server.emit('timeout');
     }));
 
diff --git a/test/parallel/test-http-client-timeout.js b/test/parallel/test-http-client-timeout.js
index bf0a3fbe54f8ce..90a3bebebc9e13 100644
--- a/test/parallel/test-http-client-timeout.js
+++ b/test/parallel/test-http-client-timeout.js
@@ -32,13 +32,13 @@ const options = {
 };
 
 const server = http.createServer(function(req, res) {
-  // this space intentionally left blank
+  // This space intentionally left blank
 });
 
 server.listen(0, options.host, function() {
   options.port = this.address().port;
   const req = http.request(options, function(res) {
-    // this space intentionally left blank
+    // This space intentionally left blank
   });
   req.on('close', function() {
     server.close();
diff --git a/test/parallel/test-http-conn-reset.js b/test/parallel/test-http-conn-reset.js
index fef75b72891e9c..e218bbfdcea3f7 100644
--- a/test/parallel/test-http-conn-reset.js
+++ b/test/parallel/test-http-conn-reset.js
@@ -38,7 +38,7 @@ const server = net.createServer(function(client) {
 });
 server.listen(0, options.host, common.mustCall(onListen));
 
-// do a GET request, expect it to fail
+// Do a GET request, expect it to fail
 function onListen() {
   options.port = this.address().port;
   const req = http.request(options, common.mustNotCall());
diff --git a/test/parallel/test-http-outgoing-finish-writable.js b/test/parallel/test-http-outgoing-finish-writable.js
index 033e9b6bc1a7db..e03901fb6ddf07 100644
--- a/test/parallel/test-http-outgoing-finish-writable.js
+++ b/test/parallel/test-http-outgoing-finish-writable.js
@@ -31,7 +31,7 @@ server.on('listening', common.mustCall(function() {
   assert.strictEqual(clientRequest.writable, true);
   clientRequest.end();
 
-  // writable is still true when close
+  // Writable is still true when close
   // THIS IS LEGACY, we cannot change it
   // unless we break error detection
   assert.strictEqual(clientRequest.writable, true);
diff --git a/test/parallel/test-http-outgoing-settimeout.js b/test/parallel/test-http-outgoing-settimeout.js
index 6e46973bc10631..3065c53f11191a 100644
--- a/test/parallel/test-http-outgoing-settimeout.js
+++ b/test/parallel/test-http-outgoing-settimeout.js
@@ -5,7 +5,7 @@ const assert = require('assert');
 const { OutgoingMessage } = require('http');
 
 {
-  // tests for settimeout method with socket
+  // Tests for settimeout method with socket
   const expectedMsecs = 42;
   const outgoingMessage = new OutgoingMessage();
   outgoingMessage.socket = {
diff --git a/test/parallel/test-http-parser.js b/test/parallel/test-http-parser.js
index 5503b2284b85fd..6d664cfc0adb90 100644
--- a/test/parallel/test-http-parser.js
+++ b/test/parallel/test-http-parser.js
@@ -179,7 +179,7 @@ function expectBody(expected) {
   let seen_body = false;
 
   const onHeaders = (headers) => {
-    assert.ok(seen_body); // trailers should come after the body
+    assert.ok(seen_body); // Trailers should come after the body
     assert.deepStrictEqual(headers,
                            ['Vary', '*', 'Content-Type', 'text/plain']);
   };
@@ -190,7 +190,7 @@ function expectBody(expected) {
     assert.strictEqual(url || parser.url, '/it');
     assert.strictEqual(versionMajor, 1);
     assert.strictEqual(versionMinor, 1);
-    // expect to see trailing headers now
+    // Expect to see trailing headers now
     parser[kOnHeaders] = mustCall(onHeaders);
   };
 
diff --git a/test/parallel/test-http-res-write-after-end.js b/test/parallel/test-http-res-write-after-end.js
index 75cb25f0a63e0c..bf6b7a3842e519 100644
--- a/test/parallel/test-http-res-write-after-end.js
+++ b/test/parallel/test-http-res-write-after-end.js
@@ -34,7 +34,7 @@ const server = http.Server(common.mustCall(function(req, res) {
   res.end();
 
   const r = res.write('This should raise an error.');
-  // write after end should return true
+  // Write after end should return true
   assert.strictEqual(r, true);
 }));
 
diff --git a/test/parallel/test-http-res-write-end-dont-take-array.js b/test/parallel/test-http-res-write-end-dont-take-array.js
index 39ac800d0d736c..f801da246edcef 100644
--- a/test/parallel/test-http-res-write-end-dont-take-array.js
+++ b/test/parallel/test-http-res-write-end-dont-take-array.js
@@ -40,7 +40,7 @@ server.once('request', common.mustCall((req, res) => {
     name: 'TypeError [ERR_INVALID_ARG_TYPE]',
   };
 
-  // write should not accept an Array
+  // Write should not accept an Array
   assert.throws(
     () => {
       res.write(['array']);
@@ -48,7 +48,7 @@ server.once('request', common.mustCall((req, res) => {
     expectedError
   );
 
-  // end should not accept an Array
+  // End should not accept an Array
   assert.throws(
     () => {
       res.end(['moo']);
@@ -64,7 +64,7 @@ server.listen(0, function() {
   // Just make a request, other tests handle responses
   http.get({ port: this.address().port }, (res) => {
     res.resume();
-    // do it again to test .end(Buffer);
+    // Do it again to test .end(Buffer);
     http.get({ port: server.address().port }, (res) => {
       res.resume();
       server.close();
diff --git a/test/parallel/test-http-server-multiheaders2.js b/test/parallel/test-http-server-multiheaders2.js
index a8878d29518f9a..95ee5b61fa916d 100644
--- a/test/parallel/test-http-server-multiheaders2.js
+++ b/test/parallel/test-http-server-multiheaders2.js
@@ -65,7 +65,7 @@ const multipleForbidden = [
   'Location',
   'Max-Forwards',
 
-  // special case, tested differently
+  // Special case, tested differently
   // 'Content-Length',
 ];
 
diff --git a/test/parallel/test-http-set-trailers.js b/test/parallel/test-http-set-trailers.js
index 3252ac7fc0af2a..9068ef8f769937 100644
--- a/test/parallel/test-http-set-trailers.js
+++ b/test/parallel/test-http-set-trailers.js
@@ -36,7 +36,7 @@ const server = http.createServer(function(req, res) {
 server.listen(0);
 
 
-// first, we test an HTTP/1.0 request.
+// First, we test an HTTP/1.0 request.
 server.on('listening', function() {
   const c = net.createConnection(this.address().port);
   let res_buffer = '';
@@ -66,7 +66,7 @@ server.on('listening', function() {
   });
 });
 
-// now, we test an HTTP/1.1 request.
+// Now, we test an HTTP/1.1 request.
 server.on('listening', function() {
   const c = net.createConnection(this.address().port);
   let res_buffer = '';
diff --git a/test/parallel/test-http-url.parse-basic.js b/test/parallel/test-http-url.parse-basic.js
index e68df80e9151d7..e03f39aa9035eb 100644
--- a/test/parallel/test-http-url.parse-basic.js
+++ b/test/parallel/test-http-url.parse-basic.js
@@ -29,7 +29,7 @@ let testURL;
 
 // make sure the basics work
 function check(request) {
-  // default method should still be get
+  // Default method should still be 'GET'
   assert.strictEqual(request.method, 'GET');
   // There are no URL params, so you should not see any
   assert.strictEqual(request.url, '/');
diff --git a/test/parallel/test-http-url.parse-search.js b/test/parallel/test-http-url.parse-search.js
index 111cf97874b4d3..d10713f5f1a7cb 100644
--- a/test/parallel/test-http-url.parse-search.js
+++ b/test/parallel/test-http-url.parse-search.js
@@ -26,7 +26,7 @@ const http = require('http');
 const url = require('url');
 
 function check(request) {
-  // a path should come over with params
+  // A path should come over with params
   assert.strictEqual(request.url, '/asdf?qwer=zxcv');
 }
 
diff --git a/test/parallel/test-http-writable-true-after-close.js b/test/parallel/test-http-writable-true-after-close.js
index a1915dd69c5da8..c0db7c34492762 100644
--- a/test/parallel/test-http-writable-true-after-close.js
+++ b/test/parallel/test-http-writable-true-after-close.js
@@ -18,7 +18,7 @@ const server = createServer(common.mustCall((req, res) => {
 
   // on CentOS 5, 'finish' is emitted
   res.on('finish', listener);
-  // everywhere else, 'close' is emitted
+  // Everywhere else, 'close' is emitted
   res.on('close', listener);
 
   get(`http://127.0.0.1:${internal.address().port}`, common.mustCall((inner) => {
diff --git a/test/parallel/test-http2-client-destroy.js b/test/parallel/test-http2-client-destroy.js
index 6c4adfe5b449c3..e7ea37e1528ef6 100644
--- a/test/parallel/test-http2-client-destroy.js
+++ b/test/parallel/test-http2-client-destroy.js
@@ -49,7 +49,7 @@ const Countdown = require('../common/countdown');
   }));
 }
 
-// test destroy before client operations
+// Test destroy before client operations
 {
   const server = h2.createServer();
   server.listen(0, common.mustCall(() => {
@@ -81,7 +81,7 @@ const Countdown = require('../common/countdown');
     common.expectsError(() => client.settings({}), sessionError);
     common.expectsError(() => client.goaway(), sessionError);
     common.expectsError(() => client.request(), sessionError);
-    client.close();  // should be a non-op at this point
+    client.close();  // Should be a non-op at this point
 
     // Wait for setImmediate call from destroy() to complete
     // so that state.destroyed is set to true
@@ -91,7 +91,7 @@ const Countdown = require('../common/countdown');
       common.expectsError(() => client.settings({}), sessionError);
       common.expectsError(() => client.goaway(), sessionError);
       common.expectsError(() => client.request(), sessionError);
-      client.close();  // should be a non-op at this point
+      client.close();  // Should be a non-op at this point
     });
 
     req.resume();
diff --git a/test/parallel/test-http2-client-priority-before-connect.js b/test/parallel/test-http2-client-priority-before-connect.js
index a9615d2cd69f12..7aa13a5e45418e 100644
--- a/test/parallel/test-http2-client-priority-before-connect.js
+++ b/test/parallel/test-http2-client-priority-before-connect.js
@@ -7,7 +7,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall((stream) => {
   stream.respond();
   stream.end('ok');
diff --git a/test/parallel/test-http2-client-settings-before-connect.js b/test/parallel/test-http2-client-settings-before-connect.js
index ceea1bc39ad7d3..ce888bb4416c09 100644
--- a/test/parallel/test-http2-client-settings-before-connect.js
+++ b/test/parallel/test-http2-client-settings-before-connect.js
@@ -7,7 +7,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall((stream, headers, flags) => {
   stream.respond();
   stream.end('ok');
diff --git a/test/parallel/test-http2-client-shutdown-before-connect.js b/test/parallel/test-http2-client-shutdown-before-connect.js
index bd971ebf7de69c..7e6a1a55c1d40a 100644
--- a/test/parallel/test-http2-client-shutdown-before-connect.js
+++ b/test/parallel/test-http2-client-shutdown-before-connect.js
@@ -7,7 +7,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustNotCall());
 
 server.listen(0, common.mustCall(() => {
diff --git a/test/parallel/test-http2-client-socket-destroy.js b/test/parallel/test-http2-client-socket-destroy.js
index 3eb7e898edcfc1..a91c6da28d1813 100644
--- a/test/parallel/test-http2-client-socket-destroy.js
+++ b/test/parallel/test-http2-client-socket-destroy.js
@@ -13,7 +13,7 @@ const body =
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall((stream) => {
   stream.on('aborted', common.mustCall());
   stream.on('close', common.mustCall());
diff --git a/test/parallel/test-http2-client-write-before-connect.js b/test/parallel/test-http2-client-write-before-connect.js
index 6588d7dccd139d..6efefc5870e75f 100644
--- a/test/parallel/test-http2-client-write-before-connect.js
+++ b/test/parallel/test-http2-client-write-before-connect.js
@@ -8,7 +8,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall((stream, headers, flags) => {
   let data = '';
   stream.setEncoding('utf8');
diff --git a/test/parallel/test-http2-cookies.js b/test/parallel/test-http2-cookies.js
index 275fbf05e79460..fcd6b847587470 100644
--- a/test/parallel/test-http2-cookies.js
+++ b/test/parallel/test-http2-cookies.js
@@ -14,7 +14,7 @@ const setCookie = [
   'e=f'
 ];
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-create-client-session.js b/test/parallel/test-http2-create-client-session.js
index 35de927ea7924e..b2d6ddbe7a03e1 100644
--- a/test/parallel/test-http2-create-client-session.js
+++ b/test/parallel/test-http2-create-client-session.js
@@ -13,7 +13,7 @@ const body =
 const server = h2.createServer();
 const count = 100;
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream, count));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-createwritereq.js b/test/parallel/test-http2-createwritereq.js
index 1575424d1609b4..3015ad6c642801 100644
--- a/test/parallel/test-http2-createwritereq.js
+++ b/test/parallel/test-http2-createwritereq.js
@@ -24,7 +24,7 @@ const encodings = {
   'ucs-2': 'ucs2',
   'utf16le': 'ucs2',
   'utf-16le': 'ucs2',
-  'UTF8': 'utf8' // should fall through to Buffer.from
+  'UTF8': 'utf8' // Should fall through to Buffer.from
 };
 
 const testsToRun = Object.keys(encodings).length;
diff --git a/test/parallel/test-http2-info-headers.js b/test/parallel/test-http2-info-headers.js
index 132818c4090037..ec95a9d3d93185 100644
--- a/test/parallel/test-http2-info-headers.js
+++ b/test/parallel/test-http2-info-headers.js
@@ -8,7 +8,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 const status101regex =
diff --git a/test/parallel/test-http2-methods.js b/test/parallel/test-http2-methods.js
index a291bdf00800d5..143b50b66b4dff 100644
--- a/test/parallel/test-http2-methods.js
+++ b/test/parallel/test-http2-methods.js
@@ -11,7 +11,7 @@ const server = h2.createServer();
 const methods = [undefined, 'GET', 'POST', 'PATCH', 'FOO', 'A B C'];
 let expected = methods.length;
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream, expected));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-no-wanttrailers-listener.js b/test/parallel/test-http2-no-wanttrailers-listener.js
index 87bc21df48aa2c..09293f2584a4ef 100644
--- a/test/parallel/test-http2-no-wanttrailers-listener.js
+++ b/test/parallel/test-http2-no-wanttrailers-listener.js
@@ -7,7 +7,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-options-max-headers-block-length.js b/test/parallel/test-http2-options-max-headers-block-length.js
index 0706e6a83e6d48..18f72bf1defb22 100644
--- a/test/parallel/test-http2-options-max-headers-block-length.js
+++ b/test/parallel/test-http2-options-max-headers-block-length.js
@@ -8,7 +8,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustNotCall());
 server.listen(0, common.mustCall(() => {
 
diff --git a/test/parallel/test-http2-options-max-reserved-streams.js b/test/parallel/test-http2-options-max-reserved-streams.js
index 6dbf54bf31c980..44c495b8330480 100644
--- a/test/parallel/test-http2-options-max-reserved-streams.js
+++ b/test/parallel/test-http2-options-max-reserved-streams.js
@@ -15,7 +15,7 @@ const countdown = new Countdown(3, () => {
   client.close();
 });
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall((stream) => {
   // The first pushStream will complete as normal
   stream.pushStream({
diff --git a/test/parallel/test-http2-perf_hooks.js b/test/parallel/test-http2-perf_hooks.js
index 4264915294827c..0fcbc323e01301 100644
--- a/test/parallel/test-http2-perf_hooks.js
+++ b/test/parallel/test-http2-perf_hooks.js
@@ -62,7 +62,7 @@ const body =
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-priority-event.js b/test/parallel/test-http2-priority-event.js
index fe04ffb342d70d..41ec6534b2de53 100644
--- a/test/parallel/test-http2-priority-event.js
+++ b/test/parallel/test-http2-priority-event.js
@@ -8,7 +8,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onPriority(stream, parent, weight, exclusive) {
diff --git a/test/parallel/test-http2-respond-file-fd-errors.js b/test/parallel/test-http2-respond-file-fd-errors.js
index 078d0eb11e451d..9508cfae9799c0 100644
--- a/test/parallel/test-http2-respond-file-fd-errors.js
+++ b/test/parallel/test-http2-respond-file-fd-errors.js
@@ -29,7 +29,7 @@ const fd = fs.openSync(fname, 'r');
 const server = http2.createServer();
 
 server.on('stream', common.mustCall((stream) => {
-  // should throw if fd isn't a number
+  // Should throw if fd isn't a number
   Object.keys(types).forEach((type) => {
     if (type === 'number') {
       return;
diff --git a/test/parallel/test-http2-respond-file-fd-invalid.js b/test/parallel/test-http2-respond-file-fd-invalid.js
index 7630b93bc63942..64c8ba541fb2a9 100644
--- a/test/parallel/test-http2-respond-file-fd-invalid.js
+++ b/test/parallel/test-http2-respond-file-fd-invalid.js
@@ -26,7 +26,7 @@ server.on('stream', (stream) => {
   try {
     while (fs.fstatSync(++fd));
   } catch {
-    // do nothing; we now have an invalid fd
+    // Do nothing; we now have an invalid fd
   }
 
   stream.respondWithFD(fd);
diff --git a/test/parallel/test-http2-respond-nghttperrors.js b/test/parallel/test-http2-respond-nghttperrors.js
index d720ec1fa486f7..3bdfbffeec4e3c 100644
--- a/test/parallel/test-http2-respond-nghttperrors.js
+++ b/test/parallel/test-http2-respond-nghttperrors.js
@@ -13,7 +13,7 @@ const {
 } = internalBinding('http2');
 const { NghttpError } = require('internal/http2/util');
 
-// tests error handling within respond
+// Tests error handling within respond
 // - every other NGHTTP2 error from binding (should emit stream error)
 
 const specificTestKeys = [];
diff --git a/test/parallel/test-http2-server-errors.js b/test/parallel/test-http2-server-errors.js
index eeb9e79682e344..fec6cc84bec72a 100644
--- a/test/parallel/test-http2-server-errors.js
+++ b/test/parallel/test-http2-server-errors.js
@@ -41,7 +41,7 @@ const h2 = require('http2');
       };
       const request = client.request(headers);
       request.on('data', common.mustCall(function(chunk) {
-        // cause an error on the server side
+        // Cause an error on the server side
         client.destroy();
       }));
       request.end();
@@ -81,7 +81,7 @@ const h2 = require('http2');
       };
       const request = client.request(headers);
       request.on('data', common.mustCall(function(chunk) {
-        // cause an error on the server side
+        // Cause an error on the server side
         client.destroy();
       }));
       request.end();
diff --git a/test/parallel/test-http2-server-push-stream-errors.js b/test/parallel/test-http2-server-push-stream-errors.js
index fb6fc11b63f999..35d8b796e47adc 100644
--- a/test/parallel/test-http2-server-push-stream-errors.js
+++ b/test/parallel/test-http2-server-push-stream-errors.js
@@ -13,7 +13,7 @@ const {
 } = internalBinding('http2');
 const { NghttpError } = require('internal/http2/util');
 
-// tests error handling within pushStream
+// Tests error handling within pushStream
 // - NGHTTP2_ERR_STREAM_ID_NOT_AVAILABLE (should emit session error)
 // - NGHTTP2_ERR_STREAM_CLOSED (should emit stream error)
 // - every other NGHTTP2 error from binding (should emit stream error)
diff --git a/test/parallel/test-http2-server-push-stream-head.js b/test/parallel/test-http2-server-push-stream-head.js
index 35e22c0ce3b561..c1db3ce81e4108 100644
--- a/test/parallel/test-http2-server-push-stream-head.js
+++ b/test/parallel/test-http2-server-push-stream-head.js
@@ -21,7 +21,7 @@ server.on('stream', common.mustCall((stream, headers) => {
     }, common.mustCall((err, push, headers) => {
       assert.strictEqual(push._writableState.ended, true);
       push.respond();
-      // cannot write to push() anymore
+      // Cannot write to push() anymore
       push.on('error', common.expectsError({
         type: Error,
         code: 'ERR_STREAM_WRITE_AFTER_END',
diff --git a/test/parallel/test-http2-server-rst-before-respond.js b/test/parallel/test-http2-server-rst-before-respond.js
index e7218aaeea29af..78fca25a82c1f8 100644
--- a/test/parallel/test-http2-server-rst-before-respond.js
+++ b/test/parallel/test-http2-server-rst-before-respond.js
@@ -8,7 +8,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-server-shutdown-before-respond.js b/test/parallel/test-http2-server-shutdown-before-respond.js
index 33f224fc69a9d5..65dd853f8392c2 100644
--- a/test/parallel/test-http2-server-shutdown-before-respond.js
+++ b/test/parallel/test-http2-server-shutdown-before-respond.js
@@ -7,7 +7,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-http2-server-socket-destroy.js b/test/parallel/test-http2-server-socket-destroy.js
index 99595aeb63004d..e7fbc2ceb7d1b3 100644
--- a/test/parallel/test-http2-server-socket-destroy.js
+++ b/test/parallel/test-http2-server-socket-destroy.js
@@ -11,7 +11,7 @@ const { kSocket } = require('internal/http2/util');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream) {
diff --git a/test/parallel/test-http2-timeouts.js b/test/parallel/test-http2-timeouts.js
index de8311a1491da8..3a75d63580e1cc 100644
--- a/test/parallel/test-http2-timeouts.js
+++ b/test/parallel/test-http2-timeouts.js
@@ -7,7 +7,7 @@ const h2 = require('http2');
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall((stream) => {
   stream.setTimeout(1, common.mustCall(() => {
     stream.respond({ ':status': 200 });
diff --git a/test/parallel/test-http2-trailers.js b/test/parallel/test-http2-trailers.js
index bdc0931157ad58..98b9b5d4a09fac 100644
--- a/test/parallel/test-http2-trailers.js
+++ b/test/parallel/test-http2-trailers.js
@@ -12,7 +12,7 @@ const trailerValue = 'testing';
 
 const server = h2.createServer();
 
-// we use the lower-level API here
+// We use the lower-level API here
 server.on('stream', common.mustCall(onStream));
 
 function onStream(stream, headers, flags) {
diff --git a/test/parallel/test-https-agent-create-connection.js b/test/parallel/test-https-agent-create-connection.js
index c174f90d7df131..c0b50cef01abe4 100644
--- a/test/parallel/test-https-agent-create-connection.js
+++ b/test/parallel/test-https-agent-create-connection.js
@@ -74,7 +74,7 @@ function createServer() {
   }));
 }
 
-// use port and host and option connect
+// Use port and host and option connect
 {
   const server = createServer();
   server.listen(0, common.mustCall(() => {
diff --git a/test/parallel/test-intl.js b/test/parallel/test-intl.js
index c55f554b00f55a..255bf066aa0ff8 100644
--- a/test/parallel/test-intl.js
+++ b/test/parallel/test-intl.js
@@ -23,7 +23,7 @@
 const common = require('../common');
 const assert = require('assert');
 
-// does node think that i18n was enabled?
+// Does node think that i18n was enabled?
 let enablei18n = process.config.variables.v8_enable_i18n_support;
 if (enablei18n === undefined) {
   enablei18n = 0;
diff --git a/test/parallel/test-listen-fd-ebadf.js b/test/parallel/test-listen-fd-ebadf.js
index 3ec40b5c23a1f2..351500be2824f1 100644
--- a/test/parallel/test-listen-fd-ebadf.js
+++ b/test/parallel/test-listen-fd-ebadf.js
@@ -35,7 +35,7 @@ let invalidFd = 2;
 try {
   while (fs.fstatSync(++invalidFd));
 } catch {
-  // do nothing; we now have an invalid fd
+  // Do nothing; we now have an invalid fd
 }
 
 net.createServer(common.mustNotCall()).listen({ fd: invalidFd })
diff --git a/test/parallel/test-microtask-queue-run-immediate.js b/test/parallel/test-microtask-queue-run-immediate.js
index 4d998cf0b8a59c..2d4e21f83aa6ef 100644
--- a/test/parallel/test-microtask-queue-run-immediate.js
+++ b/test/parallel/test-microtask-queue-run-immediate.js
@@ -41,7 +41,7 @@ setImmediate(function() {
 });
 
 
-// no nextTick, microtask with nextTick
+// No nextTick, microtask with nextTick
 setImmediate(function() {
   let called = false;
 
diff --git a/test/parallel/test-microtask-queue-run.js b/test/parallel/test-microtask-queue-run.js
index 85eb770da1e0ff..7a1667819f6758 100644
--- a/test/parallel/test-microtask-queue-run.js
+++ b/test/parallel/test-microtask-queue-run.js
@@ -41,7 +41,7 @@ setTimeout(function() {
 }, 0);
 
 
-// no nextTick, microtask with nextTick
+// No nextTick, microtask with nextTick
 setTimeout(function() {
   let called = false;
 
diff --git a/test/parallel/test-module-relative-lookup.js b/test/parallel/test-module-relative-lookup.js
index c5350e11facda4..e9d6112da752f8 100644
--- a/test/parallel/test-module-relative-lookup.js
+++ b/test/parallel/test-module-relative-lookup.js
@@ -2,7 +2,7 @@
 
 const common = require('../common');
 const assert = require('assert');
-const _module = require('module'); // avoid collision with global.module
+const _module = require('module'); // Avoid collision with global.module
 
 // Current directory gets highest priority for local modules
 function testFirstInPath(moduleName, isLocalModule) {
diff --git a/test/parallel/test-net-keepalive.js b/test/parallel/test-net-keepalive.js
index 9cc08af8fe4372..d91ec625f88246 100644
--- a/test/parallel/test-net-keepalive.js
+++ b/test/parallel/test-net-keepalive.js
@@ -38,7 +38,7 @@ const echoServer = net.createServer(function(connection) {
   }, 1), common.platformTimeout(100));
   connection.setTimeout(0);
   assert.notStrictEqual(connection.setKeepAlive, undefined);
-  // send a keepalive packet after 50 ms
+  // Send a keepalive packet after 50 ms
   connection.setKeepAlive(true, common.platformTimeout(50));
   connection.on('end', function() {
     connection.end();
diff --git a/test/parallel/test-net-persistent-keepalive.js b/test/parallel/test-net-persistent-keepalive.js
index 85a2950273a6a3..b25162996e1bd0 100644
--- a/test/parallel/test-net-persistent-keepalive.js
+++ b/test/parallel/test-net-persistent-keepalive.js
@@ -25,7 +25,7 @@ echoServer.listen(0);
 
 echoServer.on('listening', function() {
   clientConnection = new net.Socket();
-  // send a keepalive packet after 1000 ms
+  // Send a keepalive packet after 1000 ms
   // and make sure it persists
   const s = clientConnection.setKeepAlive(true, 400);
   assert.ok(s instanceof net.Socket);
diff --git a/test/parallel/test-net-server-connections-child-null.js b/test/parallel/test-net-server-connections-child-null.js
index 46084404c87661..bf75826fddb15b 100644
--- a/test/parallel/test-net-server-connections-child-null.js
+++ b/test/parallel/test-net-server-connections-child-null.js
@@ -33,7 +33,7 @@ if (process.argv[2] === 'child') {
       const connect = net.connect(server.address().port);
 
       connect.on('close', common.mustCall(() => {
-        // now server.connections should be null
+        // `server.connections` should now be null.
         assert.strictEqual(server.connections, null);
         server.close();
       }));
diff --git a/test/parallel/test-path-join.js b/test/parallel/test-path-join.js
index a9fb5b1e927552..6243d97ce8a8bc 100644
--- a/test/parallel/test-path-join.js
+++ b/test/parallel/test-path-join.js
@@ -8,7 +8,7 @@ const backslashRE = /\\/g;
 
 const joinTests = [
   [ [path.posix.join, path.win32.join],
-    // arguments                     result
+    // Arguments                     result
     [[['.', 'x/b', '..', '/b/c.js'], 'x/b/c.js'],
      [[], '.'],
      [['/.', 'x/b', '..', '/b/c.js'], '/x/b/c.js'],
@@ -64,7 +64,7 @@ const joinTests = [
 joinTests.push([
   path.win32.join,
   joinTests[0][1].slice(0).concat(
-    [// arguments                     result
+    [// Arguments                     result
       // UNC path expected
       [['//foo/bar'], '\\\\foo\\bar\\'],
       [['\\/foo/bar'], '\\\\foo\\bar\\'],
diff --git a/test/parallel/test-path-relative.js b/test/parallel/test-path-relative.js
index 26521bc088a8f7..5d5d118cc6f45c 100644
--- a/test/parallel/test-path-relative.js
+++ b/test/parallel/test-path-relative.js
@@ -7,7 +7,7 @@ const failures = [];
 
 const relativeTests = [
   [ path.win32.relative,
-    // arguments                     result
+    // Arguments                     result
     [['c:/blah\\blah', 'd:/games', 'd:\\games'],
      ['c:/aaaa/bbbb', 'c:/aaaa', '..'],
      ['c:/aaaa/bbbb', 'c:/cccc', '..\\..\\cccc'],
diff --git a/test/parallel/test-path-resolve.js b/test/parallel/test-path-resolve.js
index 79c2d679204007..e9e6d83ff54007 100644
--- a/test/parallel/test-path-resolve.js
+++ b/test/parallel/test-path-resolve.js
@@ -28,7 +28,7 @@ const resolveTests = [
     ]
   ],
   [ path.posix.resolve,
-    // arguments                    result
+    // Arguments                    result
     [[['/var/lib', '../', 'file/'], '/var/file'],
      [['/var/lib', '/../', 'file/'], '/file'],
      [['a/b/c/', '../../..'], process.cwd()],
diff --git a/test/parallel/test-preload.js b/test/parallel/test-preload.js
index 3d754accae8a8c..326eed030ca1bb 100644
--- a/test/parallel/test-preload.js
+++ b/test/parallel/test-preload.js
@@ -25,14 +25,14 @@ const fixtureC = fixtures.path('printC.js');
 const fixtureD = fixtures.path('define-global.js');
 const fixtureThrows = fixtures.path('throws_error4.js');
 
-// test preloading a single module works
+// Test preloading a single module works
 childProcess.exec(`"${nodeBinary}" ${preloadOption([fixtureA])} "${fixtureB}"`,
                   function(err, stdout, stderr) {
                     assert.ifError(err);
                     assert.strictEqual(stdout, 'A\nB\n');
                   });
 
-// test preloading multiple modules works
+// Test preloading multiple modules works
 childProcess.exec(
   `"${nodeBinary}" ${preloadOption([fixtureA, fixtureB])} "${fixtureC}"`,
   function(err, stdout, stderr) {
@@ -78,7 +78,7 @@ stdinProc.on('close', function(code) {
   assert.strictEqual(stdinStdout, 'A\nhello\n');
 });
 
-// test that preload can be used with repl
+// Test that preload can be used with repl
 const replProc = childProcess.spawn(
   nodeBinary,
   ['-i', '--require', fixtureA],
@@ -109,7 +109,7 @@ childProcess.exec(
   }
 );
 
-// test that preload works with -i
+// Test that preload works with -i
 const interactive = childProcess.exec(
   `"${nodeBinary}" ${preloadOption([fixtureD])}-i`,
   common.mustCall(function(err, stdout, stderr) {
diff --git a/test/parallel/test-process-env.js b/test/parallel/test-process-env.js
index e1be9c6e1bf3fb..0e06306634c3e2 100644
--- a/test/parallel/test-process-env.js
+++ b/test/parallel/test-process-env.js
@@ -59,7 +59,7 @@ if (process.argv[2] === 'you-are-the-child') {
   child.stderr.on('data', function(data) { console.log(data.toString()); });
   child.on('exit', function(statusCode) {
     if (statusCode !== 0) {
-      process.exit(statusCode);  // failed assertion in child process
+      process.exit(statusCode);  // Failed assertion in child process
     }
   });
 }
diff --git a/test/parallel/test-process-kill-pid.js b/test/parallel/test-process-kill-pid.js
index e69be183fb7469..c299ceabaa674e 100644
--- a/test/parallel/test-process-kill-pid.js
+++ b/test/parallel/test-process-kill-pid.js
@@ -97,7 +97,7 @@ kill('0', undefined, 0, 15);
 kill(0, 1, 0, 1);
 kill(0, 15, 0, 15);
 
-// negative numbers are meaningful on unix
+// Negative numbers are meaningful on unix
 kill(-1, 'SIGHUP', -1, 1);
 kill(-1, undefined, -1, 15);
 kill('-1', 'SIGHUP', -1, 1);
diff --git a/test/parallel/test-querystring.js b/test/parallel/test-querystring.js
index 175098aed77575..b26f41a4663c8b 100644
--- a/test/parallel/test-querystring.js
+++ b/test/parallel/test-querystring.js
@@ -269,7 +269,7 @@ qsWeirdObjects.forEach((testCase) => {
   assert.strictEqual(qs.stringify(testCase[0]), testCase[1]);
 });
 
-// invalid surrogate pair throws URIError
+// Invalid surrogate pair throws URIError
 common.expectsError(
   () => qs.stringify({ foo: '\udc00' }),
   {
diff --git a/test/parallel/test-readline-interface.js b/test/parallel/test-readline-interface.js
index 90cb8f1584f04b..fba215e225b03d 100644
--- a/test/parallel/test-readline-interface.js
+++ b/test/parallel/test-readline-interface.js
@@ -61,7 +61,7 @@ function isWarned(emitter) {
 }
 
 {
-  // set crlfDelay to float 100.5ms
+  // Set crlfDelay to float 100.5ms
   const fi = new FakeInput();
   const rli = new readline.Interface({
     input: fi,
@@ -172,7 +172,7 @@ function isWarned(emitter) {
     rli.close();
   }
 
-  // sending multiple newlines at once
+  // Sending multiple newlines at once
   {
     const fi = new FakeInput();
     const rli = new readline.Interface(
@@ -288,7 +288,7 @@ function isWarned(emitter) {
     }), delay * 2);
   }
 
-  // set crlfDelay to `Infinity` is allowed
+  // Set crlfDelay to `Infinity` is allowed
   {
     const fi = new FakeInput();
     const delay = 200;
@@ -515,7 +515,7 @@ function isWarned(emitter) {
     rli.close();
   }
 
-  // calling readline without `new`
+  // Calling readline without `new`
   {
     const fi = new FakeInput();
     const rli = readline.Interface(
@@ -661,13 +661,13 @@ function isWarned(emitter) {
       });
       fi.emit('data', '💻');
 
-      // move left one character/code point
+      // Move left one character/code point
       fi.emit('keypress', '.', { name: 'left' });
       let cursorPos = rli._getCursorPos();
       assert.strictEqual(cursorPos.rows, 0);
       assert.strictEqual(cursorPos.cols, 0);
 
-      // move right one character/code point
+      // Move right one character/code point
       fi.emit('keypress', '.', { name: 'right' });
       cursorPos = rli._getCursorPos();
       assert.strictEqual(cursorPos.rows, 0);
@@ -695,7 +695,7 @@ function isWarned(emitter) {
       });
       fi.emit('data', '💻');
 
-      // move left one character/code point
+      // Move left one character/code point
       fi.emit('keypress', '.', { name: 'left' });
       let cursorPos = rli._getCursorPos();
       assert.strictEqual(cursorPos.rows, 0);
@@ -731,7 +731,7 @@ function isWarned(emitter) {
       });
       fi.emit('data', '💻');
 
-      // move left one character/code point
+      // Move left one character/code point
       fi.emit('keypress', '.', { name: 'right' });
       let cursorPos = rli._getCursorPos();
       assert.strictEqual(cursorPos.rows, 0);
@@ -1104,7 +1104,7 @@ function isWarned(emitter) {
   assert.strictEqual(internalReadline.getStringWidth('안녕하세요'), 10);
   assert.strictEqual(internalReadline.getStringWidth('A\ud83c\ude00BC'), 5);
 
-  // check if vt control chars are stripped
+  // Check if vt control chars are stripped
   assert.strictEqual(
     internalReadline.stripVTControlCharacters('\u001b[31m> \u001b[39m'),
     '> '
diff --git a/test/parallel/test-repl-autolibs.js b/test/parallel/test-repl-autolibs.js
index f069d8bf409799..976cad84361d03 100644
--- a/test/parallel/test-repl-autolibs.js
+++ b/test/parallel/test-repl-autolibs.js
@@ -37,10 +37,10 @@ function test1() {
     gotWrite = true;
     if (data.length) {
 
-      // inspect output matches repl output
+      // Inspect output matches repl output
       assert.strictEqual(data,
                          `${util.inspect(require('fs'), null, 2, false)}\n`);
-      // globally added lib matches required lib
+      // Globally added lib matches required lib
       assert.strictEqual(global.fs, require('fs'));
       test2();
     }
@@ -57,7 +57,7 @@ function test2() {
     if (data.length) {
       // repl response error message
       assert.strictEqual(data, '{}\n');
-      // original value wasn't overwritten
+      // Original value wasn't overwritten
       assert.strictEqual(val, global.url);
     }
   };
diff --git a/test/parallel/test-repl-context.js b/test/parallel/test-repl-context.js
index 378af1c14445e8..001e2ffd4e1ede 100644
--- a/test/parallel/test-repl-context.js
+++ b/test/parallel/test-repl-context.js
@@ -41,14 +41,14 @@ const stream = new ArrayStream();
   assert.ok(!server.underscoreAssigned);
   assert.strictEqual(server.lines.length, 0);
 
-  // an assignment to '_' in the repl server
+  // An assignment to '_' in the repl server
   server.write('_ = 500;\n');
   assert.ok(server.underscoreAssigned);
   assert.strictEqual(server.lines.length, 1);
   assert.strictEqual(server.lines[0], '_ = 500;');
   assert.strictEqual(server.last, 500);
 
-  // use the server to create a new context
+  // Use the server to create a new context
   const context = server.createContext();
 
   // Ensure that creating a new context does not
diff --git a/test/parallel/test-repl-history-navigation.js b/test/parallel/test-repl-history-navigation.js
index 562b79dae846d4..b00f932aa9a253 100644
--- a/test/parallel/test-repl-history-navigation.js
+++ b/test/parallel/test-repl-history-navigation.js
@@ -50,7 +50,7 @@ const DOWN = { name: 'down' };
 const prompt = '> ';
 
 const tests = [
-  { // creates few history to navigate for
+  { // Creates few history to navigate for
     env: { NODE_REPL_HISTORY: defaultHistoryPath },
     test: [ 'let ab = 45', ENTER,
             '555 + 909', ENTER,
diff --git a/test/parallel/test-repl-save-load.js b/test/parallel/test-repl-save-load.js
index 2c42788be6ffcc..74841d86ff6ec0 100644
--- a/test/parallel/test-repl-save-load.js
+++ b/test/parallel/test-repl-save-load.js
@@ -49,7 +49,7 @@ putIn.run(testFile);
 // save it to a file
 putIn.run([`.save ${saveFileName}`]);
 
-// the file should have what I wrote
+// The file should have what I wrote
 assert.strictEqual(fs.readFileSync(saveFileName, 'utf8'),
                    `${testFile.join('\n')}\n`);
 
@@ -104,7 +104,7 @@ putIn.write = function(data) {
 };
 putIn.run([`.load ${loadFile}`]);
 
-// throw error on loading directory
+// Throw error on loading directory
 loadFile = tmpdir.path;
 putIn.write = function(data) {
   assert.strictEqual(data, `Failed to load:${loadFile} is not a valid file\n`);
diff --git a/test/parallel/test-repl-tab-complete.js b/test/parallel/test-repl-tab-complete.js
index b28923a49b1a5d..558b6cab47e2ae 100644
--- a/test/parallel/test-repl-tab-complete.js
+++ b/test/parallel/test-repl-tab-complete.js
@@ -384,7 +384,7 @@ testMe.complete('var log = console.lo', common.mustCall((error, data) => {
   assert.deepStrictEqual(data, [['console.log'], 'console.lo']);
 }));
 
-// tab completion for defined commands
+// Tab completion for defined commands
 putIn.run(['.clear']);
 
 testMe.complete('.b', common.mustCall((error, data) => {
diff --git a/test/parallel/test-repl-underscore.js b/test/parallel/test-repl-underscore.js
index cbf62c3b6e0308..30f679bcb14f49 100644
--- a/test/parallel/test-repl-underscore.js
+++ b/test/parallel/test-repl-underscore.js
@@ -15,7 +15,7 @@ testError();
 function testSloppyMode() {
   const r = initRepl(repl.REPL_MODE_SLOPPY);
 
-  // cannot use `let` in sloppy mode
+  // Cannot use `let` in sloppy mode
   r.write(`_;          // initial value undefined
           var x = 10;  // evaluates to undefined
           _;           // still undefined
diff --git a/test/parallel/test-repl.js b/test/parallel/test-repl.js
index 0f88c661b2992a..0cda683aaabc47 100644
--- a/test/parallel/test-repl.js
+++ b/test/parallel/test-repl.js
@@ -32,7 +32,7 @@ const message = 'Read, Eval, Print Loop';
 const prompt_unix = 'node via Unix socket> ';
 const prompt_tcp = 'node via TCP socket> ';
 
-// absolute path to test/fixtures/a.js
+// Absolute path to test/fixtures/a.js
 const moduleFilename = fixtures.path('a');
 
 // function for REPL to run
diff --git a/test/parallel/test-setproctitle.js b/test/parallel/test-setproctitle.js
index 2ed0730eec1c80..05bdfa578dde3f 100644
--- a/test/parallel/test-setproctitle.js
+++ b/test/parallel/test-setproctitle.js
@@ -39,6 +39,6 @@ exec(cmd, common.mustCall((error, stdout, stderr) => {
   if (common.isFreeBSD || common.isOpenBSD)
     title += ` (${path.basename(process.execPath)})`;
 
-  // omitting trailing whitespace and \n
+  // Omitting trailing whitespace and \n
   assert.strictEqual(stdout.replace(/\s+$/, '').endsWith(title), true);
 }));
diff --git a/test/parallel/test-stdout-stderr-reading.js b/test/parallel/test-stdout-stderr-reading.js
index 6466366a4f07cb..57bfffa272af46 100644
--- a/test/parallel/test-stdout-stderr-reading.js
+++ b/test/parallel/test-stdout-stderr-reading.js
@@ -2,7 +2,7 @@
 const common = require('../common');
 const assert = require('assert');
 
-// verify that stdout is never read from.
+// Verify that stdout is never read from.
 const net = require('net');
 const read = net.Socket.prototype.read;
 
@@ -59,7 +59,7 @@ function parent() {
 }
 
 function child() {
-  // should not be reading *ever* in here.
+  // Should not be reading *ever* in here.
   net.Socket.prototype.read = function() {
     throw new Error('no reading allowed in child');
   };
diff --git a/test/parallel/test-stream-ispaused.js b/test/parallel/test-stream-ispaused.js
index 366d34e326ec7d..a57928f9349194 100644
--- a/test/parallel/test-stream-ispaused.js
+++ b/test/parallel/test-stream-ispaused.js
@@ -32,7 +32,7 @@ readable._read = Function();
 // Default state of a stream is not "paused"
 assert.ok(!readable.isPaused());
 
-// make the stream start flowing...
+// Make the stream start flowing...
 readable.on('data', Function());
 
 // still not paused.
diff --git a/test/parallel/test-stream-readable-emittedReadable.js b/test/parallel/test-stream-readable-emittedReadable.js
index 5b9affc59fbbf2..ba613f9e9ff19d 100644
--- a/test/parallel/test-stream-readable-emittedReadable.js
+++ b/test/parallel/test-stream-readable-emittedReadable.js
@@ -31,7 +31,7 @@ process.nextTick(common.mustCall(() => {
   readable.push('bar');
 }));
 
-// these triggers two readable events
+// These triggers two readable events
 setImmediate(common.mustCall(() => {
   readable.push('quo');
   process.nextTick(common.mustCall(() => {
diff --git a/test/parallel/test-stream-readable-event.js b/test/parallel/test-stream-readable-event.js
index 8276e7ce4db533..e248bed4b5b3e3 100644
--- a/test/parallel/test-stream-readable-event.js
+++ b/test/parallel/test-stream-readable-event.js
@@ -38,7 +38,7 @@ const Readable = require('stream').Readable;
   r.push(Buffer.from('blerg'));
 
   setTimeout(function() {
-    // we're testing what we think we are
+    // We're testing what we think we are
     assert(!r._readableState.reading);
     r.on('readable', common.mustCall());
   }, 1);
diff --git a/test/parallel/test-stream-readable-flow-recursion.js b/test/parallel/test-stream-readable-flow-recursion.js
index fed4287445e035..bac6427fb097e5 100644
--- a/test/parallel/test-stream-readable-flow-recursion.js
+++ b/test/parallel/test-stream-readable-flow-recursion.js
@@ -67,7 +67,7 @@ flow(stream, 5000, function() {
 
 process.on('exit', function(code) {
   assert.strictEqual(reads, 2);
-  // we pushed up the high water mark
+  // We pushed up the high water mark
   assert.strictEqual(stream.readableHighWaterMark, 8192);
   // Length is 0 right now, because we pulled it all out.
   assert.strictEqual(stream.readableLength, 0);
diff --git a/test/parallel/test-stream-readable-no-unneeded-readable.js b/test/parallel/test-stream-readable-no-unneeded-readable.js
index 13ee2b498c4b96..20092b57d95871 100644
--- a/test/parallel/test-stream-readable-no-unneeded-readable.js
+++ b/test/parallel/test-stream-readable-no-unneeded-readable.js
@@ -17,7 +17,7 @@ function test(r) {
         if (data) {
           wrapper.push(data);
         }
-        // else the end event should fire
+        // else: the end event should fire
       });
     },
   });
diff --git a/test/parallel/test-stream-readable-reading-readingMore.js b/test/parallel/test-stream-readable-reading-readingMore.js
index 2198a889f0584f..f5643205da0596 100644
--- a/test/parallel/test-stream-readable-reading-readingMore.js
+++ b/test/parallel/test-stream-readable-reading-readingMore.js
@@ -20,7 +20,7 @@ const Readable = require('stream').Readable;
     if (readable.readableFlowing)
       assert.strictEqual(state.readingMore, true);
 
-    // reading as long as we've not ended
+    // Reading as long as we've not ended
     assert.strictEqual(state.reading, !state.ended);
   }, 2));
 
@@ -78,7 +78,7 @@ const Readable = require('stream').Readable;
     if (readable.readableFlowing)
       assert.strictEqual(state.readingMore, true);
 
-    // reading as long as we've not ended
+    // Reading as long as we've not ended
     assert.strictEqual(state.reading, !state.ended);
   }, 2));
 
@@ -127,7 +127,7 @@ const Readable = require('stream').Readable;
   readable.on('readable', onReadable);
 
   readable.on('data', common.mustCall((data) => {
-    // reading as long as we've not ended
+    // Reading as long as we've not ended
     assert.strictEqual(state.reading, !state.ended);
   }, 2));
 
diff --git a/test/parallel/test-stream-transform-split-highwatermark.js b/test/parallel/test-stream-transform-split-highwatermark.js
index 301d81bc904231..7837b009cd6a0e 100644
--- a/test/parallel/test-stream-transform-split-highwatermark.js
+++ b/test/parallel/test-stream-transform-split-highwatermark.js
@@ -39,7 +39,7 @@ testTransform(555, 555, {
   writableHighWaterMark: 777,
 });
 
-// test highWaterMark = 0 overriding
+// Test highWaterMark = 0 overriding
 testTransform(0, 0, {
   highWaterMark: 0,
   readableHighWaterMark: 666,
diff --git a/test/parallel/test-stream-writableState-ending.js b/test/parallel/test-stream-writableState-ending.js
index ae2121f456eb4b..69afd1af5343dc 100644
--- a/test/parallel/test-stream-writableState-ending.js
+++ b/test/parallel/test-stream-writableState-ending.js
@@ -14,22 +14,22 @@ function testStates(ending, finished, ended) {
 }
 
 writable._write = (chunk, encoding, cb) => {
-  // ending, finished, ended start in false.
+  // Ending, finished, ended start in false.
   testStates(false, false, false);
   cb();
 };
 
 writable.on('finish', () => {
-  // ending, finished, ended = true.
+  // Ending, finished, ended = true.
   testStates(true, true, true);
 });
 
 const result = writable.end('testing function end()', () => {
-  // ending, finished, ended = true.
+  // Ending, finished, ended = true.
   testStates(true, true, true);
 });
 
-// end returns the writable instance
+// End returns the writable instance
 assert.strictEqual(result, writable);
 
 // ending, ended = true.
diff --git a/test/parallel/test-stream-writableState-uncorked-bufferedRequestCount.js b/test/parallel/test-stream-writableState-uncorked-bufferedRequestCount.js
index ca5d3dfb0f02bc..0cf9179ac49847 100644
--- a/test/parallel/test-stream-writableState-uncorked-bufferedRequestCount.js
+++ b/test/parallel/test-stream-writableState-uncorked-bufferedRequestCount.js
@@ -41,17 +41,17 @@ assert.strictEqual(writable._writableState.corked, 1);
 assert.strictEqual(writable._writableState.bufferedRequestCount, 2);
 
 function uncork() {
-  // second uncork flushes the buffer
+  // Second uncork flushes the buffer
   writable.uncork();
   assert.strictEqual(writable._writableState.corked, 0);
   assert.strictEqual(writable._writableState.bufferedRequestCount, 0);
 
-  // verify that end() uncorks correctly
+  // Verify that end() uncorks correctly
   writable.cork();
   writable.write('third chunk');
   writable.end();
 
-  // end causes an uncork() as well
+  // End causes an uncork() as well
   assert.strictEqual(writable._writableState.corked, 0);
   assert.strictEqual(writable._writableState.bufferedRequestCount, 0);
 }
diff --git a/test/parallel/test-stream2-readable-from-list.js b/test/parallel/test-stream2-readable-from-list.js
index 00024b91200fff..0210a1848df03a 100644
--- a/test/parallel/test-stream2-readable-from-list.js
+++ b/test/parallel/test-stream2-readable-from-list.js
@@ -52,15 +52,15 @@ function bufferListFromArray(arr) {
   }
 ]`);
 
-  // read more than the first element.
+  // Read more than the first element.
   let ret = fromList(6, { buffer: list, length: 16 });
   assert.strictEqual(ret.toString(), 'foogba');
 
-  // read exactly the first element.
+  // Read exactly the first element.
   ret = fromList(2, { buffer: list, length: 10 });
   assert.strictEqual(ret.toString(), 'rk');
 
-  // read less than the first element.
+  // Read less than the first element.
   ret = fromList(2, { buffer: list, length: 8 });
   assert.strictEqual(ret.toString(), 'ba');
 
@@ -80,15 +80,15 @@ function bufferListFromArray(arr) {
                'kuel' ];
   list = bufferListFromArray(list);
 
-  // read more than the first element.
+  // Read more than the first element.
   let ret = fromList(6, { buffer: list, length: 16, decoder: true });
   assert.strictEqual(ret, 'foogba');
 
-  // read exactly the first element.
+  // Read exactly the first element.
   ret = fromList(2, { buffer: list, length: 10, decoder: true });
   assert.strictEqual(ret, 'rk');
 
-  // read less than the first element.
+  // Read less than the first element.
   ret = fromList(2, { buffer: list, length: 8, decoder: true });
   assert.strictEqual(ret, 'ba');
 
diff --git a/test/parallel/test-stream2-set-encoding.js b/test/parallel/test-stream2-set-encoding.js
index f60e8df9e15a85..0095fa544db114 100644
--- a/test/parallel/test-stream2-set-encoding.js
+++ b/test/parallel/test-stream2-set-encoding.js
@@ -34,14 +34,14 @@ class TestReader extends R {
   _read(n) {
     setTimeout(() => {
       if (this.pos >= this.len) {
-        // double push(null) to test eos handling
+        // Double push(null) to test eos handling
         this.push(null);
         return this.push(null);
       }
 
       n = Math.min(n, this.len - this.pos);
       if (n <= 0) {
-        // double push(null) to test eos handling
+        // Double push(null) to test eos handling
         this.push(null);
         return this.push(null);
       }
diff --git a/test/parallel/test-stream2-transform.js b/test/parallel/test-stream2-transform.js
index 92e4669dd4bc2c..cd6deaabf1147e 100644
--- a/test/parallel/test-stream2-transform.js
+++ b/test/parallel/test-stream2-transform.js
@@ -402,7 +402,7 @@ const Transform = require('_stream_transform');
     }
   };
 
-  // anything except null/undefined is fine.
+  // Anything except null/undefined is fine.
   // those are "magic" in the stream API, because they signal EOF.
   const objects = [
     { foo: 'bar' },
@@ -443,7 +443,7 @@ const Transform = require('_stream_transform');
     }
   };
 
-  // anything except null/undefined is fine.
+  // Anything except null/undefined is fine.
   // those are "magic" in the stream API, because they signal EOF.
   const objects = [
     { foo: 'bar' },
diff --git a/test/parallel/test-stream2-writable.js b/test/parallel/test-stream2-writable.js
index ec8e088221277f..af38df7e684aac 100644
--- a/test/parallel/test-stream2-writable.js
+++ b/test/parallel/test-stream2-writable.js
@@ -34,7 +34,7 @@ class TestWriter extends W {
   }
 
   _write(chunk, encoding, cb) {
-    // simulate a small unpredictable latency
+    // Simulate a small unpredictable latency
     setTimeout(() => {
       this.buffer.push(chunk.toString());
       this.written += chunk.length;
@@ -73,7 +73,7 @@ for (let i = 0; i < chunks.length; i++) {
   });
 
   tw.on('finish', common.mustCall(function() {
-    //  got chunks in the right order
+    //  Got chunks in the right order
     assert.deepStrictEqual(tw.buffer, chunks);
   }));
 
diff --git a/test/parallel/test-stream3-cork-end.js b/test/parallel/test-stream3-cork-end.js
index 8403e20fb1e8b2..0cbc033a2eadc4 100644
--- a/test/parallel/test-stream3-cork-end.js
+++ b/test/parallel/test-stream3-cork-end.js
@@ -17,17 +17,17 @@ let seenChunks = [];
 let seenEnd = false;
 
 const w = new Writable();
-// lets arrange to store the chunks
+// Let's arrange to store the chunks.
 w._write = function(chunk, encoding, cb) {
-  // Stream end event is not seen before the last write
+  // Stream end event is not seen before the last write.
   assert.ok(!seenEnd);
-  // Default encoding given none was specified
+  // Default encoding given none was specified.
   assert.strictEqual(encoding, 'buffer');
 
   seenChunks.push(chunk);
   cb();
 };
-// lets record the stream end event
+// Let's record the stream end event.
 w.on('finish', () => {
   seenEnd = true;
 });
@@ -39,7 +39,7 @@ function writeChunks(remainingChunks, callback) {
   if (writeChunk) {
     setImmediate(() => {
       writeState = w.write(writeChunk);
-      // we were not told to stop writing
+      // We were not told to stop writing.
       assert.ok(writeState);
 
       writeChunks(remainingChunks, callback);
@@ -49,43 +49,43 @@ function writeChunks(remainingChunks, callback) {
   }
 }
 
-// do an initial write
+// Do an initial write.
 w.write('stuff');
-// the write was immediate
+// The write was immediate.
 assert.strictEqual(seenChunks.length, 1);
-// reset the seen chunks
+// Reset the seen chunks.
 seenChunks = [];
 
-// trigger stream buffering
+// Trigger stream buffering.
 w.cork();
 
-// write the bufferedChunks
+// Write the bufferedChunks.
 writeChunks(inputChunks, () => {
-  // should not have seen anything yet
+  // Should not have seen anything yet.
   assert.strictEqual(seenChunks.length, 0);
 
-  // trigger flush and ending the stream
+  // Trigger flush and ending the stream.
   w.end();
 
-  // stream should not ended in current tick
+  // Stream should not ended in current tick.
   assert.ok(!seenEnd);
 
-  // Buffered bytes should be seen in current tick
+  // Buffered bytes should be seen in current tick.
   assert.strictEqual(seenChunks.length, 4);
 
-  // did the chunks match
+  // Did the chunks match.
   for (let i = 0, l = expectedChunks.length; i < l; i++) {
     const seen = seenChunks[i];
-    // there was a chunk
+    // There was a chunk.
     assert.ok(seen);
 
     const expected = Buffer.from(expectedChunks[i]);
-    // it was what we expected
+    // It was what we expected.
     assert.ok(seen.equals(expected));
   }
 
   setImmediate(() => {
-    // stream should have ended in next tick
+    // Stream should have ended in next tick.
     assert.ok(seenEnd);
   });
 });
diff --git a/test/parallel/test-stream3-cork-uncork.js b/test/parallel/test-stream3-cork-uncork.js
index 5b52ec0019feea..dfb901af419803 100644
--- a/test/parallel/test-stream3-cork-uncork.js
+++ b/test/parallel/test-stream3-cork-uncork.js
@@ -17,15 +17,15 @@ let seenChunks = [];
 let seenEnd = false;
 
 const w = new Writable();
-// lets arrange to store the chunks
+// Let's arrange to store the chunks.
 w._write = function(chunk, encoding, cb) {
-  // Default encoding given none was specified
+  // Default encoding given none was specified.
   assert.strictEqual(encoding, 'buffer');
 
   seenChunks.push(chunk);
   cb();
 };
-// lets record the stream end event
+// Let's record the stream end event.
 w.on('finish', () => {
   seenEnd = true;
 });
@@ -37,7 +37,7 @@ function writeChunks(remainingChunks, callback) {
   if (writeChunk) {
     setImmediate(() => {
       writeState = w.write(writeChunk);
-      // we were not told to stop writing
+      // We were not told to stop writing.
       assert.ok(writeState);
 
       writeChunks(remainingChunks, callback);
@@ -47,40 +47,40 @@ function writeChunks(remainingChunks, callback) {
   }
 }
 
-// do an initial write
+// Do an initial write.
 w.write('stuff');
-// the write was immediate
+// The write was immediate.
 assert.strictEqual(seenChunks.length, 1);
-// reset the chunks seen so far
+// Reset the chunks seen so far.
 seenChunks = [];
 
-// trigger stream buffering
+// Trigger stream buffering.
 w.cork();
 
-// write the bufferedChunks
+// Write the bufferedChunks.
 writeChunks(inputChunks, () => {
-  // should not have seen anything yet
+  // Should not have seen anything yet.
   assert.strictEqual(seenChunks.length, 0);
 
-  // trigger writing out the buffer
+  // Trigger writing out the buffer.
   w.uncork();
 
-  // Buffered bytes should be seen in current tick
+  // Buffered bytes should be seen in current tick.
   assert.strictEqual(seenChunks.length, 4);
 
-  // did the chunks match
+  // Did the chunks match.
   for (let i = 0, l = expectedChunks.length; i < l; i++) {
     const seen = seenChunks[i];
-    // there was a chunk
+    // There was a chunk.
     assert.ok(seen);
 
     const expected = Buffer.from(expectedChunks[i]);
-    // it was what we expected
+    // It was what we expected.
     assert.ok(seen.equals(expected));
   }
 
   setImmediate(() => {
-    // the stream should not have been ended
+    // The stream should not have been ended.
     assert.ok(!seenEnd);
   });
 });
diff --git a/test/parallel/test-stream3-pause-then-read.js b/test/parallel/test-stream3-pause-then-read.js
index d514c89e013327..b86c0157062dfe 100644
--- a/test/parallel/test-stream3-pause-then-read.js
+++ b/test/parallel/test-stream3-pause-then-read.js
@@ -77,7 +77,7 @@ function readn(n, then) {
   })();
 }
 
-// then we listen to some data events
+// Then we listen to some data events
 function onData() {
   expectEndingData -= 100;
   console.error('onData');
diff --git a/test/parallel/test-string-decoder-end.js b/test/parallel/test-string-decoder-end.js
index b10756a4633fca..0c0c072eb9d653 100644
--- a/test/parallel/test-string-decoder-end.js
+++ b/test/parallel/test-string-decoder-end.js
@@ -94,7 +94,7 @@ function testBuf(encoding, buf) {
   }
   res1 += s.end();
 
-  // write the whole buffer at once.
+  // Write the whole buffer at once.
   let res2 = '';
   s = new SD(encoding);
   res2 += s.write(buf);
diff --git a/test/parallel/test-stringbytes-external.js b/test/parallel/test-stringbytes-external.js
index 9d8aa45f67895e..b66fb0960adf21 100644
--- a/test/parallel/test-stringbytes-external.js
+++ b/test/parallel/test-stringbytes-external.js
@@ -67,10 +67,10 @@ assert.strictEqual(ucs2_control, l_bin);
 const b_bin = b.toString('binary');
 assert.strictEqual(ucs2_control, b_bin);
 
-// create buffer copy from external
+// Create buffer copy from external
 const c_bin = Buffer.from(l_bin, 'latin1');
 const c_ucs = Buffer.from(b_ucs, 'ucs2');
-// make sure they're the same length
+// Make sure they're the same length
 assert.strictEqual(c_bin.length, c_ucs.length);
 // Make sure Buffers from externals are the same
 for (let i = 0; i < c_bin.length; i++) {
@@ -101,7 +101,7 @@ const PRE_3OF4_APEX = Math.ceil((EXTERN_APEX / 4) * 3) - RADIOS;
       assert.strictEqual(pumped_string[k], pumped_string2[k]);
     }
 
-    // the recoded buffer is the same?
+    // The recoded buffer is the same?
     for (let i = 0; i < decoded.length; ++i) {
       assert.strictEqual(datum[i], decoded[i]);
     }
@@ -122,7 +122,7 @@ const PRE_3OF4_APEX = Math.ceil((EXTERN_APEX / 4) * 3) - RADIOS;
       assert.strictEqual(pumped_string[k], pumped_string2[k]);
     }
 
-    // the recoded buffer is the same?
+    // The recoded buffer is the same?
     for (let i = 0; i < decoded.length; ++i) {
       assert.strictEqual(datum[i], decoded[i]);
     }
diff --git a/test/parallel/test-timers-refresh.js b/test/parallel/test-timers-refresh.js
index dd4332ab32ea70..597d5c9241947a 100644
--- a/test/parallel/test-timers-refresh.js
+++ b/test/parallel/test-timers-refresh.js
@@ -30,7 +30,7 @@ const { setUnrefTimeout } = require('internal/timers');
   strictEqual(timer.refresh(), timer);
 }
 
-// should throw with non-functions
+// Should throw with non-functions
 {
   const expectedError = {
     code: 'ERR_INVALID_CALLBACK',
diff --git a/test/parallel/test-timers-unrefed-in-callback.js b/test/parallel/test-timers-unrefed-in-callback.js
index 50e6881bd3f60b..afeb3706df4ac9 100644
--- a/test/parallel/test-timers-unrefed-in-callback.js
+++ b/test/parallel/test-timers-unrefed-in-callback.js
@@ -24,7 +24,7 @@ let counter2 = 0;
 //    it would have fired 11 more times, and the assertion in the
 //    process'exit event handler would fail.
 function Test1() {
-  // server only for maintaining event loop
+  // Server only for maintaining event loop
   const server = net.createServer().listen(0);
 
   const timer1 = setInterval(common.mustCall(() => {
@@ -43,7 +43,7 @@ function Test1() {
 // timer callback. counter2 continues to be incremented more than 11
 // until server close completed.
 function Test2() {
-  // server only for maintaining event loop
+  // Server only for maintaining event loop
   const server = net.createServer().listen(0);
 
   const timer2 = setInterval(() => {
diff --git a/test/parallel/test-timers.js b/test/parallel/test-timers.js
index e29d756cfebd08..b8733f79f54639 100644
--- a/test/parallel/test-timers.js
+++ b/test/parallel/test-timers.js
@@ -60,7 +60,7 @@ inputs.forEach((value, index) => {
   }, value);
 
   const handle = setInterval(() => {
-    clearInterval(handle); // disarm timer or we'll never finish
+    clearInterval(handle); // Disarm timer or we'll never finish
     intervals[index] = true;
   }, value);
 });
@@ -69,7 +69,7 @@ inputs.forEach((value, index) => {
 // before a timer set here for 2 ms.
 
 setTimeout(common.mustCall(() => {
-  // assert that all other timers have run
+  // Assert that all other timers have run
   inputs.forEach((value, index) => {
     assert(timeouts[index]);
     assert(intervals[index]);
diff --git a/test/parallel/test-tls-cipher-list.js b/test/parallel/test-tls-cipher-list.js
index 4a39ee9391a7c1..ddbe6a33f6409d 100644
--- a/test/parallel/test-tls-cipher-list.js
+++ b/test/parallel/test-tls-cipher-list.js
@@ -23,8 +23,8 @@ function doCheck(arg, check) {
     }).on('error', common.mustNotCall());
 }
 
-// test the default unmodified version
+// Test the default unmodified version
 doCheck([], defaultCoreList);
 
-// test the command line switch by itself
+// Test the command line switch by itself
 doCheck(['--tls-cipher-list=ABC'], 'ABC');
diff --git a/test/parallel/test-tls-env-extra-ca.js b/test/parallel/test-tls-env-extra-ca.js
index b8ff1d3be237eb..c6587ae414e440 100644
--- a/test/parallel/test-tls-env-extra-ca.js
+++ b/test/parallel/test-tls-env-extra-ca.js
@@ -39,7 +39,7 @@ const server = tls.createServer(options, common.mustCall(function(s) {
   });
 
   fork(__filename, { env }).on('exit', common.mustCall(function(status) {
-    // client did not succeed in connecting
+    // Client did not succeed in connecting
     assert.strictEqual(status, 0);
   }));
 }));
diff --git a/test/parallel/test-tls-fast-writing.js b/test/parallel/test-tls-fast-writing.js
index 937694228a5951..398beb0d097701 100644
--- a/test/parallel/test-tls-fast-writing.js
+++ b/test/parallel/test-tls-fast-writing.js
@@ -43,7 +43,7 @@ function onconnection(conn) {
       console.log('ok - got chunk');
     }
 
-    // just some basic sanity checks.
+    // Just some basic sanity checks.
     assert(c.length);
     assert(Buffer.isBuffer(c));
 
@@ -69,7 +69,7 @@ server.listen(0, function() {
     write();
   }
   function write() {
-    // this needs to return false eventually
+    // This needs to return false eventually
     while (false !== conn.write(chunk));
   }
 });
diff --git a/test/parallel/test-url-fileurltopath.js b/test/parallel/test-url-fileurltopath.js
index 9a9b751201766f..f6a1fb4fdafd01 100644
--- a/test/parallel/test-url-fileurltopath.js
+++ b/test/parallel/test-url-fileurltopath.js
@@ -93,7 +93,7 @@ assert.throws(() => url.fileURLToPath('https://a/b/c'), {
       { path: 'C:\\fóóbàr', fileURL: 'file:///C:/f%C3%B3%C3%B3b%C3%A0r' },
       // euro sign (BMP code point)
       { path: 'C:\\€', fileURL: 'file:///C:/%E2%82%AC' },
-      // rocket emoji (non-BMP code point)
+      // Rocket emoji (non-BMP code point)
       { path: 'C:\\🚀', fileURL: 'file:///C:/%F0%9F%9A%80' }
     ];
   } else {
@@ -138,7 +138,7 @@ assert.throws(() => url.fileURLToPath('https://a/b/c'), {
       { path: '/fóóbàr', fileURL: 'file:///f%C3%B3%C3%B3b%C3%A0r' },
       // euro sign (BMP code point)
       { path: '/€', fileURL: 'file:///%E2%82%AC' },
-      // rocket emoji (non-BMP code point)
+      // Rocket emoji (non-BMP code point)
       { path: '/🚀', fileURL: 'file:///%F0%9F%9A%80' },
     ];
   }
diff --git a/test/parallel/test-url-pathtofileurl.js b/test/parallel/test-url-pathtofileurl.js
index 6cdfa5dcd336ec..1beb69b7f38343 100644
--- a/test/parallel/test-url-pathtofileurl.js
+++ b/test/parallel/test-url-pathtofileurl.js
@@ -67,7 +67,7 @@ const url = require('url');
       { path: 'C:\\fóóbàr', expected: 'file:///C:/f%C3%B3%C3%B3b%C3%A0r' },
       // euro sign (BMP code point)
       { path: 'C:\\€', expected: 'file:///C:/%E2%82%AC' },
-      // rocket emoji (non-BMP code point)
+      // Rocket emoji (non-BMP code point)
       { path: 'C:\\🚀', expected: 'file:///C:/%F0%9F%9A%80' }
     ];
   } else {
@@ -112,7 +112,7 @@ const url = require('url');
       { path: '/fóóbàr', expected: 'file:///f%C3%B3%C3%B3b%C3%A0r' },
       // euro sign (BMP code point)
       { path: '/€', expected: 'file:///%E2%82%AC' },
-      // rocket emoji (non-BMP code point)
+      // Rocket emoji (non-BMP code point)
       { path: '/🚀', expected: 'file:///%F0%9F%9A%80' },
     ];
   }
diff --git a/test/parallel/test-url-relative.js b/test/parallel/test-url-relative.js
index 6bead6a30d7007..dc0362df1a5662 100644
--- a/test/parallel/test-url-relative.js
+++ b/test/parallel/test-url-relative.js
@@ -152,7 +152,7 @@ const relativeTests2 = [
   ['g#s/../x', bases[0], 'http://a/b/c/g#s/../x'],
   ['http:g', bases[0], ('http:g', 'http://a/b/c/g')],
   ['http:', bases[0], ('http:', bases[0])],
-  // not sure where this one originated
+  // Not sure where this one originated
   ['/a/b/c/./../../g', bases[0], 'http://a/a/g'],
 
   // http://gbiv.com/protocols/uri/test/rel_examples2.html
@@ -211,7 +211,7 @@ const relativeTests2 = [
   ['../../', bases[3], 'fred:///s//'],
   ['../../g', bases[3], 'fred:///s//g'],
   ['../../../g', bases[3], 'fred:///s/g'],
-  // may change to fred:///s//a/../../../g
+  // May change to fred:///s//a/../../../g
   ['../../../../g', bases[3], 'fred:///g'],
 
   // http://gbiv.com/protocols/uri/test/rel_examples5.html
@@ -229,9 +229,9 @@ const relativeTests2 = [
   ['../g', bases[4], 'http:///s//a/g'],
   ['../../', bases[4], 'http:///s//'],
   ['../../g', bases[4], 'http:///s//g'],
-  // may change to http:///s//a/../../g
+  // May change to http:///s//a/../../g
   ['../../../g', bases[4], 'http:///s/g'],
-  // may change to http:///s//a/../../../g
+  // May change to http:///s//a/../../../g
   ['../../../../g', bases[4], 'http:///g'],
 
   // From Dan Connelly's tests in http://www.w3.org/2000/10/swap/uripath.py
diff --git a/test/parallel/test-util-isDeepStrictEqual.js b/test/parallel/test-util-isDeepStrictEqual.js
index 08a30a28dbc573..071e612565938a 100644
--- a/test/parallel/test-util-isDeepStrictEqual.js
+++ b/test/parallel/test-util-isDeepStrictEqual.js
@@ -350,7 +350,7 @@ notUtilIsDeepStrict(
 
   m2.set(2, 'hi'); // different order
   m2.set(1, obj);
-  m2.set(3, [1, 2, 3]); // deep equal, but not reference equal.
+  m2.set(3, [1, 2, 3]); // Deep equal, but not reference equal.
 
   utilIsDeepStrict(m1, m2);
 }
diff --git a/test/parallel/test-v8-coverage.js b/test/parallel/test-v8-coverage.js
index 926d28f14e1a7f..5c3db7af2cfea3 100644
--- a/test/parallel/test-v8-coverage.js
+++ b/test/parallel/test-v8-coverage.js
@@ -28,7 +28,7 @@ function nextdir() {
   assert.ok(fixtureCoverage);
   // first branch executed.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[0].count, 1);
-  // second branch did not execute.
+  // Second branch did not execute.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[1].count, 0);
 }
 
@@ -44,7 +44,7 @@ function nextdir() {
   assert.ok(fixtureCoverage, 'coverage not found for file');
   // first branch executed.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[0].count, 1);
-  // second branch did not execute.
+  // Second branch did not execute.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[1].count, 0);
 }
 
@@ -62,11 +62,11 @@ function nextdir() {
   assert.ok(fixtureCoverage);
   // first branch executed.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[0].count, 1);
-  // second branch did not execute.
+  // Second branch did not execute.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[1].count, 0);
 }
 
-// outputs coverage from subprocess.
+// Outputs coverage from subprocess.
 {
   const coverageDirectory = path.join(tmpdir.path, nextdir());
   const output = spawnSync(process.execPath, [
@@ -79,7 +79,7 @@ function nextdir() {
   assert.ok(fixtureCoverage);
   // first branch executed.
   assert.strictEqual(fixtureCoverage.functions[1].ranges[0].count, 1);
-  // second branch did not execute.
+  // Second branch did not execute.
   assert.strictEqual(fixtureCoverage.functions[1].ranges[1].count, 0);
 }
 
@@ -96,7 +96,7 @@ function nextdir() {
   assert.ok(fixtureCoverage);
   // first branch executed.
   assert.strictEqual(fixtureCoverage.functions[1].ranges[0].count, 1);
-  // second branch did not execute.
+  // Second branch did not execute.
   assert.strictEqual(fixtureCoverage.functions[1].ranges[1].count, 0);
 }
 
@@ -145,7 +145,7 @@ function nextdir() {
   assert.ok(fixtureCoverage);
   // first branch executed.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[0].count, 1);
-  // second branch did not execute.
+  // Second branch did not execute.
   assert.strictEqual(fixtureCoverage.functions[0].ranges[1].count, 0);
 }
 
diff --git a/test/parallel/test-vm-global-property-interceptors.js b/test/parallel/test-vm-global-property-interceptors.js
index 8fe5f8f3da91b2..23c56018b62e1f 100644
--- a/test/parallel/test-vm-global-property-interceptors.js
+++ b/test/parallel/test-vm-global-property-interceptors.js
@@ -117,7 +117,7 @@ Object.defineProperty(this, 'encodeURI', { value: 42 });
 assert.strictEqual(vm.runInContext('encodeURI;', ctx), 42);
 assert.strictEqual(ctx.encodeURI, 42);
 
-// redefine properties on the sandbox
+// Redefine properties on the sandbox
 vm.runInContext(`
 Object.defineProperty(this, 'e', { value: 'newE' });
 `, ctx);
diff --git a/test/parallel/test-zlib-from-concatenated-gzip.js b/test/parallel/test-zlib-from-concatenated-gzip.js
index 45f8281387ceb4..7bb31c0f9ddd9f 100644
--- a/test/parallel/test-zlib-from-concatenated-gzip.js
+++ b/test/parallel/test-zlib-from-concatenated-gzip.js
@@ -81,6 +81,6 @@ fs.createReadStream(pmmFileGz)
     abcEncoded, defEncoded.slice(0, offset)
   ]));
 
-  // write remaining bytes of "def"
+  // Write remaining bytes of "def"
   unzip.end(defEncoded.slice(offset));
 });
diff --git a/test/parallel/test-zlib-from-gzip-with-trailing-garbage.js b/test/parallel/test-zlib-from-gzip-with-trailing-garbage.js
index f7b09f7ec03fca..7db3a8a27abad5 100644
--- a/test/parallel/test-zlib-from-gzip-with-trailing-garbage.js
+++ b/test/parallel/test-zlib-from-gzip-with-trailing-garbage.js
@@ -5,7 +5,7 @@ const common = require('../common');
 const assert = require('assert');
 const zlib = require('zlib');
 
-// should ignore trailing null-bytes
+// Should ignore trailing null-bytes
 let data = Buffer.concat([
   zlib.gzipSync('abc'),
   zlib.gzipSync('def'),
diff --git a/test/parallel/test-zlib-invalid-input.js b/test/parallel/test-zlib-invalid-input.js
index dbfb5235b8a908..9b22df477840cb 100644
--- a/test/parallel/test-zlib-invalid-input.js
+++ b/test/parallel/test-zlib-invalid-input.js
@@ -20,7 +20,7 @@
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 'use strict';
-// test uncompressing invalid input
+// Test uncompressing invalid input
 
 const common = require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-zlib-random-byte-pipes.js b/test/parallel/test-zlib-random-byte-pipes.js
index c7026163e77586..0816e047bb0eef 100644
--- a/test/parallel/test-zlib-random-byte-pipes.js
+++ b/test/parallel/test-zlib-random-byte-pipes.js
@@ -31,7 +31,7 @@ const zlib = require('zlib');
 
 const Stream = stream.Stream;
 
-// emit random bytes, and keep a shasum
+// Emit random bytes, and keep a shasum
 class RandomReadStream extends Stream {
   constructor(opt) {
     super();
@@ -50,7 +50,7 @@ class RandomReadStream extends Stream {
     opt.total = opt.total || 256 * 1024 * 1024;
     this._remaining = opt.total;
 
-    // how variable to make the block sizes
+    // How variable to make the block sizes
     opt.jitter = opt.jitter || 1024;
 
     this._opt = opt;
@@ -86,7 +86,7 @@ class RandomReadStream extends Stream {
       return;
     }
 
-    // figure out how many bytes to output
+    // Figure out how many bytes to output
     // if finished, then just emit end.
     let block = this._opt.block;
     const jitter = this._opt.jitter;
@@ -110,7 +110,7 @@ class RandomReadStream extends Stream {
   }
 }
 
-// a filter that just verifies a shasum
+// A filter that just verifies a shasum
 class HashStream extends Stream {
   constructor() {
     super();
diff --git a/test/parallel/test-zlib.js b/test/parallel/test-zlib.js
index d5ef9fe9d13ce7..1852ae33936452 100644
--- a/test/parallel/test-zlib.js
+++ b/test/parallel/test-zlib.js
@@ -39,7 +39,7 @@ let zlibPairs = [
 // How fast to trickle through the slowstream
 let trickle = [128, 1024, 1024 * 1024];
 
-// tunable options for zlib classes.
+// Tunable options for zlib classes.
 
 // several different chunk sizes
 let chunkSize = [128, 1024, 1024 * 16, 1024 * 1024];
@@ -144,7 +144,7 @@ class SlowStream extends stream.Stream {
   }
 
   end(chunk) {
-    // walk over the chunk in blocks.
+    // Walk over the chunk in blocks.
     this.chunk = chunk;
     this.length = chunk.length;
     this.resume();
diff --git a/test/pummel/test-net-timeout.js b/test/pummel/test-net-timeout.js
index 524322440a1ea6..59a8d50f796d64 100644
--- a/test/pummel/test-net-timeout.js
+++ b/test/pummel/test-net-timeout.js
@@ -59,7 +59,7 @@ echo_server.listen(common.PORT, () => {
 
   const client = net.createConnection(common.PORT);
   client.setEncoding('UTF8');
-  client.setTimeout(0); // disable the timeout for client
+  client.setTimeout(0); // Disable the timeout for client
   client.on('connect', () => {
     console.log('client connected.');
     client.write('hello\r\n');
diff --git a/test/pummel/test-stream-pipe-multi.js b/test/pummel/test-stream-pipe-multi.js
index 2767028c4b393b..f8fb7c9cc89cc2 100644
--- a/test/pummel/test-stream-pipe-multi.js
+++ b/test/pummel/test-stream-pipe-multi.js
@@ -64,7 +64,7 @@ FakeStream.prototype.close = function() {
 };
 
 
-// expect all streams to close properly.
+// Expect all streams to close properly.
 process.on('exit', function() {
   assert.strictEqual(wclosed, cnt);
   assert.strictEqual(rclosed, cnt);
@@ -93,8 +93,8 @@ for (let i = 0; i < cnt; i++) {
   r.pipe(w);
 }
 
-// now start passing through data
-// simulate a relatively fast async stream.
+// Now start passing through data.
+// Simulate a relatively fast async stream.
 rr.forEach(function(r) {
   let cnt = chunks;
   let paused = false;
diff --git a/test/pummel/test-timers.js b/test/pummel/test-timers.js
index 6b761f455de20e..8a8646b3237f90 100644
--- a/test/pummel/test-timers.js
+++ b/test/pummel/test-timers.js
@@ -23,11 +23,11 @@
 const common = require('../common');
 const assert = require('assert');
 
-const WINDOW = 200; // why is does this need to be so big?
+const WINDOW = 200; // Why is does this need to be so big?
 
 let interval_count = 0;
 
-// check that these don't blow up.
+// Check that these don't blow up.
 clearTimeout(null);
 clearInterval(null);
 
diff --git a/test/sequential/test-debugger-debug-brk.js b/test/sequential/test-debugger-debug-brk.js
index 65ee43061cb40c..d8c5c67c0204c9 100644
--- a/test/sequential/test-debugger-debug-brk.js
+++ b/test/sequential/test-debugger-debug-brk.js
@@ -19,7 +19,7 @@ function test(arg) {
   const fail = () => assert.fail(true, false, `'${argStr}' should not quit`);
   child.on('exit', fail);
 
-  // give node time to start up the debugger
+  // Give node time to start up the debugger
   setTimeout(function() {
     child.removeListener('exit', fail);
     child.kill();
diff --git a/test/sequential/test-deprecation-flags.js b/test/sequential/test-deprecation-flags.js
index be159ceb384ee2..1c369a0f8b361c 100644
--- a/test/sequential/test-deprecation-flags.js
+++ b/test/sequential/test-deprecation-flags.js
@@ -61,7 +61,7 @@ execFile(node, traceDep, function(er, stdout, stderr) {
   assert.strictEqual(er, null);
   assert.strictEqual(stdout, '');
   const stack = stderr.trim().split('\n');
-  // just check the top and bottom.
+  // Just check the top and bottom.
   assert(
     /util\.debug is deprecated\. Use console\.error instead\./.test(stack[1])
   );
diff --git a/test/sequential/test-http-max-http-headers.js b/test/sequential/test-http-max-http-headers.js
index b91135a61a2a5a..16704fd9124c3e 100644
--- a/test/sequential/test-http-max-http-headers.js
+++ b/test/sequential/test-http-max-http-headers.js
@@ -59,7 +59,7 @@ function writeHeaders(socket, headers) {
     last = current;
   }
 
-  // safety check we are chunking correctly
+  // Safety check we are chunking correctly
   assert.strictEqual(array.join(''), headers);
 
   next();
diff --git a/test/sequential/test-inspector.js b/test/sequential/test-inspector.js
index 9aaabdc6c95472..04381918583bc9 100644
--- a/test/sequential/test-inspector.js
+++ b/test/sequential/test-inspector.js
@@ -225,7 +225,7 @@ async function testCommandLineAPI(session) {
   checkException(result);
   assert.deepStrictEqual(JSON.parse(result.result.value),
                          { old: 'yes' });
-  // remove module from require.cache
+  // Remove module from require.cache
   result = await session.send(
     {
       'method': 'Runtime.evaluate', 'params': {
diff --git a/test/sequential/test-module-loading.js b/test/sequential/test-module-loading.js
index 9c60d15d9e93da..db9d7e9d40ec9a 100644
--- a/test/sequential/test-module-loading.js
+++ b/test/sequential/test-module-loading.js
@@ -45,7 +45,7 @@ require('../fixtures/not-main-module.js');
 }
 
 {
-  // require a file without any extensions
+  // Require a file without any extensions
   const foo_no_ext = require('../fixtures/foo');
   assert.strictEqual(foo_no_ext.foo, 'ok');
 }
@@ -154,7 +154,7 @@ require.extensions['.test'] = function(module, filename) {
 };
 
 assert.strictEqual(require('../fixtures/registerExt').test, 'passed');
-// unknown extension, load as .js
+// Unknown extension, load as .js
 assert.strictEqual(require('../fixtures/registerExt.hello.world').test,
                    'passed');
 
diff --git a/test/sequential/test-net-listen-shared-ports.js b/test/sequential/test-net-listen-shared-ports.js
index 78d94b4ae1e6b0..41345f37e66b6c 100644
--- a/test/sequential/test-net-listen-shared-ports.js
+++ b/test/sequential/test-net-listen-shared-ports.js
@@ -59,7 +59,7 @@ if (cluster.isMaster) {
   }, common.mustCall(function() {
     server2.listen({ port: common.PORT + 1, exclusive: true },
                    common.mustCall(function() {
-                     // the first worker should succeed
+                     // The first worker should succeed
                      process.send('success');
                    })
     );
diff --git a/test/sequential/test-repl-timeout-throw.js b/test/sequential/test-repl-timeout-throw.js
index 3636b93ddfc2b2..eecd7b39867104 100644
--- a/test/sequential/test-repl-timeout-throw.js
+++ b/test/sequential/test-repl-timeout-throw.js
@@ -53,7 +53,7 @@ child.stdout.once('data', function() {
 
 child.on('close', function(c) {
   assert.strictEqual(c, 0);
-  // make sure we got 3 throws, in the end.
+  // Make sure we got 3 throws, in the end.
   const lastLine = stdout.trim().split(/\r?\n/).pop();
   assert.strictEqual(lastLine, '> 3');
 });
diff --git a/tools/doc/html.js b/tools/doc/html.js
index ef15cbded87f6a..4d5e31fe9c79bb 100644
--- a/tools/doc/html.js
+++ b/tools/doc/html.js
@@ -221,7 +221,7 @@ function preprocessElements({ filename }) {
           node.children.shift();
           node.children.unshift(...paragraph.children);
 
-          // insert div with prefix and number
+          // Insert div with prefix and number
           node.children.unshift({
             type: 'html',
             value: `<div class="api_stability api_stability_${number}">` +
@@ -231,7 +231,7 @@ function preprocessElements({ filename }) {
                 .replace(/\n/g, ' ')
           });
 
-          // remove prefix and number from text
+          // Remove prefix and number from text
           text.value = explication;
 
           // close div