What does static variable mean?

There are 3 main uses for the static.

1. If you declare within a function:
It retains the value between function calls

2.If it is declared for a function name:
By default function is extern..so it will be visible from other files if the function declaration is as static..it is invisible for the outer files

3. Static for global variables:
By default we can use the global variables from outside files If it is static global..that variable is limited to with in the file.

#include  int t = 10;   main(){     int x = 0;      void funct1();     funct1();                 printf("After first call \n");     funct1();                 printf("After second call \n");     funct1();                 printf("After third call \n"); } void funct1() {     static int y = 0;       int z = 10;                  printf("value of y %d z %d",y,z);     y=y+10; }

value of y 0 z 10 After first call
      value of y 10 z 10 After second call
      value of y 20 z 10 After third call