Difference between void main and int main in C/C++?

Bjarne Stroustrup made this quite clear:

The definition void main() is not and never has been C++, nor has it even been C.

See reference.

The difference is one is the correct way to define main, and the other is not.

And yes, it does matter. Either

int main(int argc, char** argv)

or

int main()

are the proper definition of your main per the C++ spec.

void main(int argc, char** argv)

is not and was, IIRC, a perversity that came with older Microsoft's C++ compilers.

https://isocpp.org/wiki/faq/newbie#main-returns-int