NOTE:

These are a little sketchy...I'll fill in details 'soon'.

What's a Pointer?

       pointer                               variable

                                              +----+
        +---+                                 |    |
        | ----------------------------------->|    |
        +---+                                 |    |
                                              +----+

• a pointer is a variable which stores the address of another variable

• pointers allow indirect access to memory locations

• this allows us to pass the address of an entire object/array rather than having to make a copy of the whole thing (which would be time/memory intensive)

• a pointer variable is declared by placing a * in front of the variable's name:

      type var;     // normal variable
      type *pvar;   // pointer variable
  

• programmers often precede pointer variable names with a p to easily remember that it is a pointer variable

Basic Pointer Operations

• you can find out the memory address of an existing object using the unary & operator:

      object    // evaluates to the object itself
      &object   // evaluates to the address at which the object is stored
  

• you can access the value of the object of which a pointer holds the address by using the 'dereference' operator — unary *:

      p         // evaluates to the address of p's destination object
      *p        // evaluates to p's destination object itself
  

Stack vs. Heap

• the stack is a portion of memory used for function arguments and variables during program execution; it grows and shrinks as functions are called and return (respectively)
• the heap is a large section of memory controlled by the operating system