explain pointers in c. how it is declared and used code example

Example 1: poiner in c

#include <stdio.h>
int main() {
   int c = 5;
   int *p = &c;

   printf("%d", *p);  // 5
   return 0; 
}

Example 2: poiner in c

int c, *pc;

// pc is address but c is not
pc = c; // Error

// &c is address but *pc is not
*pc = &c; // Error

// both &c and pc are addresses
pc = &c;

// both c and *pc values 
*pc = c;