Glossary of Internet Terms

Letter U

©2002 by Walt Howe
(last updated 22 October 2012)


 

Select the first character of the term you want to look up or use the Search link on the right.

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This Internet Glossary is growing. Terms and definitions are being added all the time. If you have comments, corrections, or suggested additions, please send them to Walt Howe using the form at the end of the Glossary. My thanks for the many suggestions that already have been included.


Web Developers! See how to link to terms in the glossary from your web page.

U

 

Unicode
A standard character set which uses two bytes or 16 bits to code each character. Compare it to ASCII, which uses only one byte or 8 bits per character. ASCII is limited to 256 characters, enough for most European languages, but too limited for languages like Chinese and Japanese with their many characters. For more information, see the Unicode Home Page.
unix
A computer operating system widely used on computers big and small, and very commonly used on the Internet. Many of MSDOS' commands were adapted from the short, cryptic commands characteristic of unix, such as rm, cd, and mv. For more information, see the Unix FAQ and visit the Delphi Unix Forum.
upload
To transfer a file from your computer system to another system via a modem over telephone or cable lines or a telnet connection using a transfer protocol like xmodem, ymodem, zmodem, or Kermit. Less precisely, it may also refer to a direct transfer from your local terminal to a server over a local area network or an FTP transfer from your system to a remote system. See download. For help uploading HTML files and graphics to your web page, see the PubWeb FAQ.
urban legend
An oft-told tale on the Internet that is untrue, but refuses to die. They keep reappearing in newsgroups, e-mail discussion lists, and message bases. The stories themselves are interesting and when newcomers read them for the first time, they are often passed along as fact. They may have been once true as in the Craig Shergold get-well card story, a hoax like the GOOD TIMES VIRUS, or a joke, like the expensive Neiman-Marcus cookie recipe. They often appear with variations, so that get-well cards become business cards, or Neiman-Marcus becomes Mrs. Fields instead. Read more about these in our accompanying feature on Urban Legends.
URI
Universal Resource Identifier. A standardized method of identifying and locating resources which includes Uniform Resource Names (URN) and Uniform Resource Locators (URL). The system is only partly implemented today, but when fully implemented, when a URN is requested, it will be systematically matched with a set of URLs for the resource to find the best available route to the resource.

URL
Uniform Resource Locator. URLs specify the location of a resource in the Internet.You can type or paste a URL into the Location window in your browser and then connect to it. The URL shows the type of item and its basic address and path. The major types are http, gopher, ftp, telnet, newsgroups, news articles, and files, which may be programs, text, graphics, audio, video, etc. See How to Use URLs

URN
Uniform Resource Name. A standardized name for a persistent, location-independent, resource identifier. As conceived, when the system is implemented, you will be able to link to a resource by URN without specifying its location. See the W3 page on URI and URN
Usenet Newsgroups
Usenet Newsgroups are discussion groups about a topic that is reflected in their titles, such as comp.sys.ibm.pc.games.adventure or sci.astro.hubble. Many of the newsgroups have worldwide distribution, and their followers post messages, properly called "articles", for all to read and respond to. The "Usenet" part of the title refers to their distribution via the unix to unix network. Strictly speaking, newsgroups are a Usenet, not an Internet protocol, but they are widely picked up by Internet providers.

There are eight major primary series of newsgroups: comp, humanities, misc, news, rec, sci, soc, and talk. Newsgroups in the eight primary series are only created after a formal approval process, which includes formal discussion and voting. In addition, there are less formal alternative newsgroups with the alt series the primary one, and many others with a regional or local focus such as the nyc series or the uk series or topics with limited distribution and purpose like k12 or fedreg. To participate in newsgroups, you should learn the purpose and the norms of the newsgroup before posting any articles of your own. A good rule of thumb is to read for two weeks before posting, and then follow the norms. Many newsgroups post a FAQ: Frequently Asked Questions file about once a month, which you should look at before posting for the first time. See the Newsgroup FAQ for more help.


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For Web Developers: How to Link to the glossary terms.
You can link to any term in this glossary with a link in this form:

http://www.walthowe.com/glossary/*.html#term

Replace the asterisk in *.html with the first letter of the term you are linking to. Terms with more than one word will generally use an underline to link the words.