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 .


Computer programs can be written in a variety of different languages. Different languages are optimized for different tasks. Common languages include Java, C, C++, ForTran, Pascal, Lisp, and BASIC. Some people classify languages into two categories, higher-level and lower-level. These people would consider assembly language and machine language lower-level languages and all other languages higher-level. In general, higher-level languages can be either interpreted or compiled; many languages allow both, but some are restricted to one or the other. Many people do not consider machine language and assembly language at all when talking about programming languages.
A laptop is any computer designed to do pretty much anything a desktop system can do but run for a short time (usually two to five hours) on batteries. They are designed to be carried around but are not particularly convenient to carry around. They are significantly more expensive than desktop systems and have far worse battery life than PDAs. Calling a system a laptop implies nothing about its platform. By far the fastest laptops are the PowerPC based Macintoshes.


Commonly used to abbreviate the word "localization". There are ten letters between the "l" and the "n". Similar to (and often used along with) i18n.
The Lightweight Directory Access Protocol provides a means of sharing address book type of information across an intranet or even across the Internet. Note too that "address book type of information" here is pretty broad; it often includes not just human addresses, but machine addresses, printer configurations, and similar.
A selection of routines used by programmers to make computers do particular things.
Something that is lightweight will not consume computer resources (such as RAM and disk space) too much and will thus run on less expensive computer systems.
Believe it or not, one of the fastest, most robust, and powerful multitasking OSes is available for free. Linux can be downloaded for free or be purchased on CD-ROM for a small service charge. A handful of companies distribute Linux including Red Hat, Debian, Caldera, and many others. Linux is also possibly available for more hardware combinations than any other OS (with the possible exception of NetBSD. Supported processors include: Alpha, PowerPC, SPARC, x86, and 68xx. Most processors currently not supported are currently works-in-progress or even available in beta. For example, work is currently underway to provide support for PA-RISC, 65xx, StrongARM, and Z80. People have even successfully gotten Linux working on PDAs. As you may have guessed, Linux can be made quite lightweight. Linux is a variant of UNIX and as such, most of the traditional UNIX software will run on Linux. This especially includes the GNU software, most of which comes with the majority of Linux distributions. Fast, reliable, stable, and inexpensive, Linux is popular with ISPs, software developers, and home hobbyists alike.
Lisp stands for list processing and is the second oldest computer language in the world. Being developed in 1959, it lost the title to FORTRAN by only a few months. It is typically interpreted, but compilers are available for some platforms. Attempts were made to standardize the language, and the standard version is called "Common Lisp". There have also been efforts to simplify the language, and the results of these efforts is another language called Scheme. Lisp is a fairly portable language, but is not particularly fast. Today, Lisp is most widely used with AI software.
There are two popular meanings for load. The first means to fetch some data or a program from a disk and store it in memory. The second indicates the amount of work a component (especially a processor) is being made to do.
Logo is an interpreted language designed by Papert in 1966 to be a tool for helping people (especially kids) learn computer programming concepts. In addition to being used for that purpose, it is often used as a language for controlling mechanical robots and other similar devices. Logo interfaces even exist for building block / toy robot sets. Logo uses a special graphics cursor called "the turtle", and Logo is itself sometimes called "Turtle Graphics". Logo is quite portable but not particularly fast. Versions can be found on almost every computer platform in the world. Additionally, some other languages (notably some Pascal versions) provide Logo-like interfaces for graphics-intensive programming.
If a process is lossy, it means that a little quality is lost when it is performed. If a format is lossy, it means that putting data into that format (or possibly even manipulating it in that format) will cause some slight loss. Lossy processes and formats are typically used for performance or resource utilization reasons. The opposite of lossy is lossless.
Lua is a simple interpreted language. It is extremely portable, and free versions exist for most platforms.