# Iterator Design Pattern

## 1. Intent

* Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
* The C++ and Java standard library abstraction that makes it possible to decouple collection classes and algorithms.
* Promote to "full object status" the traversal of a collection
* Polymorphic traversal

## 2. Problem

Need to "abstract" the traversal of wildly different data structures so that algorithms can be defined that are capable of interfacing with each transparently.