main() in C, C++, Java, C#

Question

Is main() (or Main()) in C, C++, Java or C#, a user-defined function or a built-in function?

Answer 1

It's declaration is built-in. It's definition is user supplied, or in some cases supplied by an application framework that has some other entry point, or in the case of most event-driven GUI frameworks, no single user-defined entry point.