/* File: my1stprog.c    */
/* My first C program   */
/* Author: Sergey Sadov */
/* Date: Fri Sept.9 2005 */
/* This program prints a greeting */

int main()
{
  printf("%s", "Hello, everybody!\n");
  return(0);
}

To compile:

     gcc my1stprog.c

As a result, the file a.out is created (or updated, if it existed before). If the program contained syntax error(s), the compiler would report them instead of creating (or updating) the file a.out

Examples of syntax errors:

Example of a small non-syntax mistake:

Example of a style deficiency (has no effect to compilability and functionality, but makes reading the program more difficult):