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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U3

a platform for running Windows 2000 or XP applications directly from a USB drive. Known as "smart drive computing" by the U3 initiative, founded in 2004 by M-Systems and SanDisk, U3 lets users run their own U3-enabled applications on any Windows computer without installing or storing any data or settings on the computer. U3 applications can be set to launch immediately when the USB drive is inserted, and when removed, there is no data or altered settings left on the computer. For more information, visit www.u3.com

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UDP

(User Datagram Protocol) a protocol within the TCP/IP protocol suite that is used in place of TCP when a reliable delivery is not required. There is less processing of UDP packets than there is for TCP. UDP is widely used for streaming audio and video, voice over IP (VoIP) and videoconferencing, because there is no time to retransmit erroneous or dropped packets.

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UI

(User Interface) the part of an application the user experiences as opposed to the internal functioning of the program.

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undo

a command included in many word processing and graphics software applications that allows a user to eliminate or reverse the last action. For example, say you’ve just applied a moustache to the Mona Lisa with your new paint program. You then decide you like the painting better the way it was originally. With a click of the undo button or command, the moustache is gone. In many Windows compatible programs, pressing the Ctrl and Z keys together will accomplish the same thing as the undo feature.

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undocumented

features included in a program that were not described in the users manual. Sometimes undocumented items are left out unintentionally. Sometimes undocumented features were present to facilitate the writing of the program by the designers and programmers and thought to be unimportant to the end-user. Other times, such features are present as part of a test in determining whether they will be included in future versions of the program.

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UNIX

a multitasking, multi-user, operating system created by Ken Thompson and Dennis Ritchie along with a small team at Bell Laboratories in the early 1970s. Although felt to be user un-friendly, UNIX evolved over the years and has become popular. Because it was originally distributed in its source language format, anyone could make modifications to the system. Today there are two major versions of the program, System V, produced by Bell Labs and BSD4.x, developed at Berkley University.

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unpack

to convert a compressed file to its original form.

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upgrade

a newer version of a software program or hardware device. Software upgrades are usually less expensive than buying the entire program new, however, one must be able to prove he has bought the earlier version to qualify for the upgrade. When installing the upgrade the new features can be thought of as being “overlaid” onto the previous version. As computer technology rapidly advances, both hardware and software becomes dated quickly. Many times, people feel the need to own the latest devices and software without regard to what it will be used for (the earlier version works well for the intended use). Operating speeds are often among the most important features included in upgrades of all types.

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upload

opposite of download, to transfer files to another computer via a network. For example, a Web designer, would publish newly created pages (upload) to a server that would store them for users to call up and view.

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uppercase

keyboard characters that are “large” or written in capitals such as X YZ, as opposed to small letters, x y z. The term dates back to the early days of printing when the capital letter characters were stored in drawers (cases) above the small letters.