A financial report is made up of disclosures. A disclousre can be organized into topics.
A topic is a useful category into which a diclosure can be organized.
The FASB uses topics to organize disclosures in their Accounting Standards Codification (ASC), see https://asc.fasb.org/.
However, the FASB list of topics is incomplete because it does not include common practice topics. The IASB likewise provides a list of topics. And likewise, the IASB list is incomplete because it also does not include common practice topics.