In C, any function that is declared with void, for example void main() can not return a value. However, functions that are declared with int, float or charMUST return a value.

#include"stdio.h"
int main()
{
	printf("Hacker World");
	printf("Hacker World Again");
	printf("Programmers World");
	return 0;                     // also use getch();  
}
/* dev c++ softwere me void main() support nhi krta hai aap turbo c++ me void main() bhi use kr skte hai
 #include<conio.h> aap use nhi krte hai aur getch(); use krenge to error aayega */

return 0 and getch() are two different things in C programming:

1. return 0 is a statement used to indicate that a function (usually the main function) has completed successfully and to return a value to the operating system. The value 0 is commonly used to indicate success, but other values can also be used to indicate different types of errors or status codes.

int main() {
    // code to be executed
    return 0;
}

2. getch() is a function that reads a single character from the keyboard without waiting for the user to press the Enter key. This function is not a part of the standard C library, but is provided by the conio.h header file which is non standard. It is mostly used in the Turbo C compiler.

#include <conio.h>
int main() {
    char c = getch();
    // code to be executed
    return 0;
}

In other words return 0 is used at the end of the main function to indicate successful termination of the program and getch() is used to read a single character from the keyboard without displaying it on the screen.

Thanks