*.cpp and *.h files understanding
So i have programmed in C++ for many years now, i know OOP and stuff that comes with it. But there's only one stupid thing that i don't understand :
What are cpp files used for ? ( I know that i need to create "main.cpp" but for the rest cpp files, couldn't they work even if they are h )
I know that when you include header file, everything from that file is copyed to where it's included. So does this work for cpp files ? Could you include cpp file ?
Are cpp files executed on them selfs without including anything ? ( Just like main.cpp )
In what order are those files executed ? Is main first or last ?
Why aren't variables in cpp same as variables in h ?
Please tell me if you know anything !
Anything related to cpp files would help...