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=== Pointers to Pointers ===
Named "double indirection"

"indirection" refers to indirect actions eg. an action is performed on the address to which a pointer points to.
"double indirection" means indirect action on an indirect action

* Syntax is similar
Declarations use an extra " * " eg.
<Pre>int **ptr</Pre>
meaning pointer to a pointer of int, or address of pointer is stored in another pointer

Example:

First declaring 3 int objects:
* A number 2
* Pointer to int
* Pointer to a pointer to int
<Pre>
int num = 2;
int *ptrONE;
int **ptrTWO;
</Pre>

Points the first pointer to the number 2
<Pre>
ptrONE = &num;
</Pre>

Points the second pointer to the first pointer
<Pre>
ptrTWO = &ptrONE;
</Pre>

This concept can be applied as many times as you want.

Example: Pointer to pointer of a pointer

<Pre>
int num = 2;
int *ptrONE
int **ptrTWO
int ***ptrTHREE

ptrONE = &num;
ptrTWO = &ptrONE;
ptrTHREE = &ptrTWO;
</Pre>

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