What is the purpose of main() function

In C, program execution starts from the main() function. Every C program must contain a main() function. The main function may contain any number of statements. These statements are executed sequentially in the order which they are written.

The main function can in-turn call other functions. When main calls a function, it passes the execution control to that function. The function returns control to main when a return statement is executed or when end of function is reached.

In C, the function prototype of the ‘main’ is one of the following:

int main(); //main with no arguments
int main(int argc, char *argv[]); //main with arguments

The parameters argc and argv respectively give the number and value of the program’s command-line arguments.

Example:

#include<stdio.h>
/* program section begins here */
int main() {
 // opening brace - program execution starts here
 printf("Welcome to the world of C");
 return 0;
}// closing brace - program terminates here

Output:

Welcome to the world of C