Why do I need ILK, PDB and EXP files?

Question

I have downloaded some dll files and with it came also pdb, exp and ilk files. Now I need to know do I need to put them in my system file, or not and what is the purpose of each of them in the general?

Answer 1

PDB files contain debug information and are useful if you need to step through the DLL's code at any point.

ILK files are used by the linker. They are not needed unless the DLL is to be recompiled.

EXP files contain information about things exported from the DLL