macOS Default int main arguments in C/C++

[sheepopo39]

I was messing around with projects in xcode with C/C++ and I notcied this

#include <iostream.h>

int main (int argc, const char * argv[]) {
    // insert code here...
    cout << "Hello, World!\n";
    return 0;
}

C++

and

#include <stdio.h>

int main (int argc, const char * argv[]) {
    // insert code here...
    printf("Hello, World!\n");
    return 0;
}

C

So I've always sort of wondered about this, what exactly do those default arguments do in C/C++ under int main? I know that the application will still compile without them, but what purpose do they serve?

 

[chown33]

Search Wikipedia for argv:

http://en.wikipedia.org/wiki/Command-line_argument

http://en.wikipedia.org/wiki/Main_function_(programming)