What exactly is the purpose of the (asterisk) in pointers?

Question

I'm new to programming and I'm trying to wrap my head around the idea of 'pointers'.

---

int main()
{
    int x = 5;
    int *pointerToInteger = & x;
    cout<<pointerToInteger;

}

Why is it that when I cout << pointerToInteger; the output is a hexdecimal value, BUT when I use cout << *pointerToInteger; the output is 5 ( x=5).

Answer 1

* has different meaning depending on the context.

1. Declaration of a pointer

   int* ap;  // It defines ap to be a pointer to an int.
   
   void foo(int* p); // Declares function foo.
                     // foo expects a pointer to an int as an argument.
   

2. Dereference a pointer in an expression.

   int i = 0;
   int* ap = &i;   // ap points to i
   *ap = 10;       // Indirectly sets the value of i to 10
   

3. A multiplication operator.

   int i = 10*20; // Needs no explanation.