Glossary
Import table and IAT
The PE structures that list the DLL functions a program needs; the loader resolves them and writes their addresses into the import address table (IAT).
The import directory has one descriptor per DLL, each pointing to a list of functions imported by name (with a hint) or by ordinal. When the program loads, Windows resolves every function and writes its address into the import address table (IAT), which the code calls through.
Imports are a quick overview of capabilities: networking, process injection, registry, cryptography. Delay-load imports are resolved on first use instead, and packed programs import very little and resolve the rest at run time. The ordered import list is the basis of the imphash.