static_data_example.c

#include <stdio.h>
#include <stdlib.h>

int counter = 0;    // global var

int main(int argc, char** argv) {
  counter++;
  printf("count = %d\n",counter);
  return EXIT_SUCCESS;
}

stack_data_example.c

#include <stdio.h>
#include <stdlib.h>

int foo(int a) {
  int x = a + 1;     // local var
  return x;
}

int main(int argc, char** argv) {
  int y = foo(10);   // local var
  printf("y = %d\n",y);
  return EXIT_SUCCESS;
}