test.cpp

int main(int argc, char *argv[]) {
  int *p;
  int x = 20;
  int y = 10;
  p = x;  // compile error
  p = &x;
  int *pp = &y; // pp points to y, *pp value is equal to 10 and pp holds y address
  int **ppp; // making pointer which points to another pointer
  cout << *p << endl; // prints 20
  ppp = &p;
  cout << *ppp << endl;  // prints 20
  cout << p << endl; // prints x address
  cout << &p << endl; // prints p address
  p++; // increases current p address 2 bytes (ints)
  *p++; // increases the value of x
  ++*p; // increases the value of x
  *p = y; // value of y will be copied to p, so x will be changed to 10
  *p = &y; // address of y will be copied to p, so x will be changed to y address
  p =  &y; // p points to y
  return 0;
}