Global variables are helpful when many functions in the program use the same data. Storage for global variables is in a fixed region of memory set aside for this purpose by the compiler.

In the following program, the variable count has been declared outside of all functions.

Example:

#include "stdio.h"
int count;  /* count is global  */
void func1(void);
int main(void)
{
  count = 100;
  func1();
  return 0;
}
void func1(void)
{
  printf("count is %
d", count); /* will print 100 */
}

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