Select the first letter of the word from the list above to jump to appropriate section of the glossary or type the term on which you want to search.

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X.25

a common standard for packet-switching networks.

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Xbox

a gaming machine from Microsoft intended to compete with Sony's PlayStation and Nintendo's GameCube. Introduced in 2001 with a 733MHz Pentium III CPU, 5x DVD drive and custom-designed graphics processor, the Xbox also includes four game controller ports, Ethernet networking and Internet connectivity.

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xD Picture Card

(EXtreme Digital Picture Card) a flash memory card used in digital cameras. Introduced in 2002 by Fuji and Olympus, the xD cards were the smallest on the market until the Mini SD card was announced in 2003. xD Cards provide high speed data transfer (3 to 5 Mbytes/sec), use low power and became available in capacities up to 1GB.

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Xenix

a version of the UNIX operating system developed by Microsoft for use on PCs.

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Xerox

a leader in the global document market, providing document solutions that enhance business productivity. The company’s document processing activities encompass developing, manufacturing, marketing, servicing and financing a complete range of document processing products and solutions designed to make organizations around the world more productive. In the 1970s Xerox developed devices such as the mouse and graphical user interface technology that was later adopted by Apple for use in early home computers.

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XML

(EXtensible Markup Language) an open standard for describing data from the W3C. It is used for defining data elements on a Web page and business-to-business documents. XML uses a similar tag structure as HTML; however, whereas HTML defines how elements are displayed, XML defines what those elements contain. While HTML uses predefined tags, XML allows tags to be defined by the developer of the page. By providing a common method for identifying data, XML supports business-to-business transactions and has become "the" format for electronic data interchange and Web services.

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Xmodem

a protocol for transferring blocks of data together from one computer to another developed in the 1970s by Ward Christensen. The advantage to Xmodem technology is in its ability to detect errors and to ensure that data isn’t lost during transfer.

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XSL

(eXtensible Stylesheet Language) a standard from the W3C for describing a style sheet for XML documents. It is the XML counterpart to the Cascading Style Sheets (CSS) in HTML and is also compatible with CSS2. XSL is made up of three components: (1) XSL Transformations (XSLT) is the processing language for XSL. It is used to convert XML documents into HTML or other document types and may be used independently of XSL. (2) XML Path Language (Xpath) is used to identify and select tagged elements within an XML document, and (3) XSL Formatting Objects (XSL FO) provides the format vocabulary.

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XviD

an open source video codec that is based on MPEG-4. Both XviD and DivX evolved from the Mayo open source project; however, DivX became a commercial product, while XviD (DivX backwards) is distributed under the GPL license. For more information, visit www.xvid.org.