TechDictionary.com http://www.techdictionary.com/

The Tech Dictionary is one of the most massive online compilations of
technical terms and jargon, but it has much more to offer than just
definitions. Descriptions of virtually all domain name suffixes that
appear in Web addresses (i.e., .com, .org, etc.) are given, including
those that were recently added by the Internet Corporation for Assigned
Names and Numbers. Hundreds of filename extensions are also listed for
both PC and UNIX-based operating systems. The Tech Dictionary also
serves as a news source, with links to technology and virus related
news stories updated daily.

From The NSDL Scout Report for Math, Engineering, and Technology,
Copyright Internet Scout Project 1994-2003. http://scout.wisc.edu