Is 'return 0;' is useless in c ?

Answer 1

No, It's not that useless. It prevents you to making syntax errors. Because If your function has some return type then you to return something otherwise it will give you an errors. And in the most of the cases main function has a integer return type as default that's why you have to write return 0;

Answer 2

It's also a the value returned to operative system.