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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upstream

in computing is the speed at which data can be transferred from the client to the server (uploading). This differs greatly from downstream not only in theory and usage, but also in that upstream speeds are usually at a premium. Whereas downstream is important to the average home user for purposes of downloading content, uploads are used mainly for web server applications and similar processes where the sending of data is critical.

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URI

(Uniform Resource Identifier) the addressing technology for identifying resources on the Internet or private intranet. URIs were originally defined as two types: Uniform Resource Locators (URLs) which are addresses with network locations, and Uniform Resource Names (URNs), which are persistent names that are address independent.

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URL

(Universal Resource Locator or Uniform Resource Locator) the addresses by which individuals are able to find information on the Internet. The first component of the address indicates what protocol is to be used such as http:// The next part of the address is the location of the document, such as wwwfor World Wide Web. The remaining elements point to the particular document stored on a server.

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USB

(Universal Serial Bus) a widely used hardware interface for attaching peripheral devices. USB ports began to appear on PCs in 1997, and Windows 98 was the first Windows to support it natively. Within a few years, USB became popular for connecting nearly every external peripheral device. Replacing the serial and parallel ports on a PC, at least four USB ports are standard on every computer.

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USB 1.0

has a maximum bandwidth of 12 Mbps

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USB 2.0

(Hi-Speed USB) has a maximum bandwidth of 480 Mbps

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USB drive

1. a flash memory card that plugs into the computer's USB port. Small enough to hook onto a key chain, it emulates a small disk drive and allows data to be easily transferred from one machine to another.
2. a USB drive may also refer to a portable hard disk, CD or DVD drive that plugs into the computer's USB port. In this case, it has nothing to do with flash storage.

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Usenet

a collection of newsgroups (discussion forums) that can be accessed through many online services as well as the Internet, that discuss more than 15,000 topics. The rules of netiquette are usually strictly observed in these groups.

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user

an individual, with an experience level that might vary from novice to expert, who operates a computer and/or other hardware devices.

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user interface

the means by which an individual communicates with a computer through a software application. The common methods for such communication are, commands, menus, and icons. see interface.