Whats the function the library windows.h on c?
windows.h is not a library, it is a header file. A header file is a text file that the C compiler reads as it is compiling your code. A library file is a binary file that the linker reads after your C code is compiled. The linker produces the final .exe program from the output of the C compiler and libraries it uses. Windows.h is just a text file, so you can find it on your machine, open it up and have a look. It isn’t very big by itself, but it does include a number of other header files (which you can also open and read). Combined, they define the Windows API that your program can use. There are many, many functions in the Windows API that you can call, and these header files will define them all for you. All the structs and constants and enum’s and other things you need to work with the Windows API are also defined in these files. And they may even direct the C compiler to add libraries for the linker.