Keypress and what will happen then?

[piccolo]

Also check out the msdn online library it is THE reference you need:
msdn.microsoft.com/en-us/library/windows/desktop/ms644985(v=vs.85).aspx
and also on codeproject: www.codeproject.com/Articles/1264/KeyBoard-Hooks
The SetWindowsHookEx routine. Be aware that you need a 64 bit version AND a 32 bit version if you want to run it on a 64 bit windows, otherwise you are not able to hook the 32 bits programs. Anyway codeproject has a whole set on hooks: www.codeproject.com/KB/DLL/#Hooks
Have fun with it, it is not that difficult...
I suggest that if you only want to hook the keyboard to not use dll injection of lower level api hooking. This may trigger antivirus programs and bock your program.