X400           Another method of sending Email other than SMTP. An X400 address
               is split into sub-sections.


X500           A directory protocol used to traverse databases or directory services
               such as SQL, Active Directory, NDS, Exchange etc.


XBox           First game console by Microsoft which uses a Penium III processor, Nvidea
               NA2A GPU, CD/DVD drive and hard disk.


XBox 360       Second generation game console by Microsoft with a PPC Tri-core Xenon processor,
               ATI Xenos GPU with a CD/DVD drive and Hard drive. 
               
Xeon           High end Intel processor used mainly for servers which can use 2 or
               more processors on the motherboard.

XGA            Entended Graphics Adapter. IBMs latest screen technology at 1024 x 768.

XHTML          Extensible HTML. Used as a bridge between standard HTML and XML.

XML            Extensible Markup Language. A metalanguage used to describe other
               documents, databases etc.

XP             Microsoft's eXPerience brand name for 2001 edition of 
               Office and Windows.

XSL            Extensible Style Sheet for XML documents for formatting and
               filtering of XML documents.

XSLT           Extensible Sort and fiLtering language for XML.

XT             Early models of IBM PCs using 8088/8086 processors.

X Windows      Windows system used by Unix based systems e.g. Linux.