Is main a user defined function or pre defined function??

main is predefined function in C programing like in Java main is predefined method and also you can make your own function.

The prototype is predefine and the implementation is user defined. For nearly all practical purposes, main is the entry point of your program, but in reality the main entry point is defined by C/C++ runtime libraries it could be like _main, _crtmain, _wmain etc this function then calls user implemented main function and if not found signals the error.

main is predefined function!!!!!!