ndiswrapper is an implementation of Network Driver Interface Specification (NDIS) for Linux kernel. With this, NDIS drivers can be used in Linux kernel to support chipsets that have no native implementation or not well supported in Linux.
Current implementation supports many chipsets / drivers that use NDIS 5. Windows XP drivers are implemented with NDIS 5.
There is an (incomplete) implementation NDIS 6 (used in Windows 7, 10), but it is not useful to end users as of now.