Introduction

In a hash table, elements are mapped to their storage location based on their search key.  This differs from a sorted array/binary tree in that the storage location does not (initially) depend on the other elements being stored.  As a result, it should be possible to have direct access to the storage location for each element.  Subsequently, hash tables can be a very fast data structure to store things in.
 

Resources

• If you would like to watch a demo of a hash table, try this example.  You should be able to observe the differences between linear and quadratic probing.  Also, notice that duplicate keys are not allowed.  (Turn the animation off to makes things run faster.)