On a server, an alias maps an incoming request for a Web page. When an alias is found in a URL, the alias' value is substituted in place of the alias. For example, if you have Web pages on a server that you wish to display on the Internet, the actual location of those files may be "http://www.well.com/user/silly" but with the use of an alias, you can tell people to access the site at "http://www.well.com/~silly" -- in this case, the tilde (~) represents an alias for the path, /user/.
NetLingo Classification: Technical Terms
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