Do we always need to return from the main function?

Question

We have two types of main declaration i.e.

void main()
and
int main()

I want to know the difference between these two and when to use what?

Answer 1

Default signature of main function is
int main(void) or int main(int argc, char *argv[])
when user use one of the above mentioned prototype, it tells that main return exist status to Operating system.
If programmer has nothing to return to O.S, he/she can typecast explicitly. I mean to say in place of int main , can use void main.

Answer 2

When your program becomes a process then OS/script like to see the return value of the process so that it can take the corrective action for that purpose you can return as return 0 or return 1. That is the reason why we have return type as int in the main function.

FYI 1 is treated as success and 0 as failure.