// Declare a pointer variable called iPtr pointing to an int (an int pointer)
// It contains an address. That address holds an int value.
int *int_Ptr;

// Declare a pointer of type double.
double *double_Ptr;

// Initializes a to the integer value 5
int a = 5;
// Set int_Ptr which is an int pointer to the address of `a`.
int *int_Ptr = &a
// Returns the address of `a`.
std::cout << int_Ptr;
// Returns 5 because it dereference the pointer to retrieve the value of `a`.
std::cout << *int_Ptr;