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 .


Anything visually displayed on a computer that is not text.


A gateway connects otherwise separate computer networks.
The graphic environment operating system is a lightweight OS with a GUI. It runs on several different processors, including the 65xx (different versions for different machines -- there are versions for the C64, the C128, and the Apple ][, each utilizing the relevant custom chip sets), the x86 (although the x86 version is made to run on top of MS-DOS (or PC-DOS or DR-DOS) and is not strictly a full OS or a window manager, rather it is somewhat in between, like Windows 3.1) and numerous different PDAs, embedded devices, and hand-held machines. It was originally designed by Berkeley Softworks (no real relation to the Berkeley of UNIX fame) but is currently in a more interesting state: the company GeoWorks develops and promotes development of GEOS for hand-held devices, PDAs, & and embedded devices and owns (but has ceased further development on) the x86 version. The other versions are owned (and possibly still being developed) by the company CMD.
GHz & gigahertz
One gigahertz is equivalent to 1000 megahertz, or 1,000,000,000 hertz.
A virtual machine optimized for running interactive fiction, interactive tutorials, and other interactive things of a primarily textual nature. Glulx has been ported to several platforms, and in in many ways an upgrade to the Z-machine.
The GNU network object model environment is a popular free window manager (and much more -- as its name touts, it is more of a desktop environment) that runs under X-Windows. It is a part of the GNU project.
GNU stands for GNU's not UNIX and is thus a recursive acronym (and unlike the animal name, the "G" here is pronounced). At any rate, the GNU project is an effort by the Free Software Foundation (FSF) to make all of the traditional UNIX utilities free for whoever wants them. The Free Software Foundation programmers know their stuff, and the quality of the GNU software is on par with the best produced commercially, and often better. All of the GNU software can be downloaded for free or obtained on CD-ROM for a small service fee. Documentation for all GNU software can be downloaded for free or obtained in book form for a small service fee. The Free Software Foundation pays its bills from the collection of service fees and the sale of T-shirts, and exists mostly through volunteer effort. It is based in Cambridge, MA.
Go is a compiled object-oriented language influenced by C, C++, C#, and Java.
Though not as popular as FTP or http, the gopher protocol is implemented by many browsers and numerous other programs and allows the transfer of files across networks. In some respects it can be thought of as a hybrid between FTP and http, although it tends not to be as good at raw file transfer as FTP and is not as flexible as http. The collection of documents available through gopher is often called "gopherspace", and it should be noted that gopherspace is older than the web. It should also be noted that gopher is not getting as much attention as it once did, and surfing through gopherspace is a little like exploring a ghost town, but there is an interesting VR interface available for it, and some things in gopherspace still have not been copied onto the web.
A graphical user interface is a graphics-based means of communicating with a program, especially an OS or window manager. In fact, a window manager can be thought of as a GUI for a CLI OS.