It's mostly Visual C++ I think. I have Visual C++ 6 Standard and the code for many controls is included to help you find errors in your code that microsoft put there
For reference, it's located in the VC98\MFC\SRC directory.
It seems to be the only part of Windows we'll ever see if it don't go open source :|
And guys, if it was all done in basic, how would VC++ work? Your werent thinking if you didnt get void main's joke. How fast is basic? It's slow assss heeeeellllllll. Quick my ass :\
And Bob 11: Stallman, I have RedHat 5.2 and 6.0 (single cd distros) if you want