Windows API functions

Question

Are they standard code c or c++ code? what are they?

Answer 1

The original Win32 API is C-based. There are however a substantial number of services within Windows that are COM based. Good examples are the clipboard, drag+drop, the shell, the user mode driver framework, DirectX. While it is technically possible to write COM code in C, it is excruciatingly painful to do so.

Realistically you use C++ there. And a C++ class library to make the original C-based API less painful, especially for GUI code.