Glossary of Computer Terms

Computer Terms Glossary

This page is meant to serve as a guide to the vast quantity of computer terms and acronyms in common use for the casual computer user. It is divided into two main sections, the first is dedicated to the basics and is meant more for beginners, while the second is meant instead to be used as a reference. In reality many of the terms in the second section are still quite common; the first section was deliberately kept as short as possible.

Terms in the second section may be looked up by either using the "find in page" function of your browser, or by appending "#term" (without the quotes and where term is the term of interest) to the "URL" or "go to" section of your browser, keeping in mind that case matters. The best method of searching for a term though is to use the Search Interface that will return not only the specific term sought but also other entries that reference it. Be aware that the terms referenced in the second part of this page will freely assume familiarity with the first part.

If you are instead actually trying to figure out what a particular filename extension means, you might instead try the filename extensions page.

If you want something added or see a problem with something already here (but keep in mind this guide is not meant to be overly technical) please send .


X-Faces are small monochrome images embedded in headers for both provides a e-mail and news messages. Better mail and news applications will display them (sometimes automatically, sometimes only per request).
X-Windows provides a GUI for most UNIX systems, but can also be found as an add-on library for other computers. Numerous window managers run on top of it. It is often just called "X".
Extensible 3D Graphics data is an XML file that is used to hold three-dimensional graphical data. It is the successor to VRML.
The x86 series of processors includes the Pentium, Pentium Pro, Pentium II, Pentium III, Celeron, and Athlon as well as the 786, 686, 586, 486, 386, 286, 8086, 8088, etc. It is an exceptionally popular design (by far the most popular CISC series) in spite of the fact that even its fastest model is significantly slower than the assorted RISC processors. Many different OSes run on machines built around x86 processors, including MS-DOS, Windows 3.1, Windows '95, Windows '98, Windows ME, Windows NT, Windows 2000, Windows CE, Windows XP, GEOS, Linux, Solaris, OpenBSD, NetBSD, FreeBSD, Mac OS X, OS/2, BeOS, CP/M, etc. A couple different companies produce x86 processors, but the bulk of them are produced by Intel. It is expected that this processor will eventually be completely replaced by the Merced, but the Merced development schedule is somewhat behind. Also, it should be noted that the Pentium III processor has stirred some controversy by including a "fingerprint" that will enable individual computer usage of web pages etc. to be accurately tracked.
An XML Binding Language document is used to associate executable content with an XML tag. It is itself an XML file, and is used most frequently (although not exclusively) in conjunction with XUL.
The Extensible Hypertext Mark-up Language is essentially a cleaner, stricter version of HTML. It is a proper subset of XML.
The Extensible Mark-up Language is a subset of SGML and a superset of XHTML. It is used for numerous things including (among many others) RSS and RDF.
XML-RPC provides a fairly lightweight means by which one computer can execute a program on a co-operating machine across a network like the Internet. It is based on XML and is used for everything from fetching stock quotes to checking weather forcasts.
The energy-efficient, kid-friendly laptop produced by the OLPC project. It runs Sugar for its window manager and Linux for its OS. It sports numerous built-in features like wireless networking, a video camera & microphone, a few USB ports, and audio in/out jacks. It comes with several educational applications (which it refers to as "Activities"), most of which are written in Python.
The Extensible Stylesheet Language is like CSS for XML. It provides a means of describing how an XML resource should be displayed.
XSL Transformations are used to transform one type of XML into another. It is a component of XSL that can be (and often is) used independently.
An XML User-Interface Language document is used to define a user interface for an application using XML to specify the individual controls as well as the overall layout.