http://interactiveasp.net/blogs/natesstuff/archive/2010/01/15/strong-hashing.aspxThere are three main tools used in cryptography.  They are hashing, synchronous encryption, and asynchronous encryption.  A very superficial definition could be: Hashing – Creating a unique value based on blocks of input. Even a minor changeenCommunityServer 2008 (Build: 30417.1769)