Web cache

(1) A computer system in a network that keeps copies of the most-recently requested Web pages in memory or on disk in order to speed up retrieval. If the next page requested has already been stored in the cache, it is retrieved locally rather than from the Internet. Web caching servers (or caching servers or cache servers) sit inside the company's firewall and enable all popular pages retrieved by users to be instantly available. Since the content of Web pages can change, the caching software is always checking for newer versions of the page and downloading them. Pages will be deleted from the cache after a set amount of non-activity. See browser cache, proxy cache, reverse proxy cache, transparent cache. See also Akamai.

Caching Appliance

This NetCache model from Network Appliance is a "caching appliance," because it plugs into the network and performs one function: Web caching. This C6100 model holds up to two terabytes of Web pages. (Image courtesy of Network Appliance, Inc.)

(2) The storehouse of pages maintained by your Web browser for a period of time. Options in your browser let you set the amount of disk space used and length of time before pages expire and are deleted. In Internet Explorer, select Tools/Internet Options. In Netscape, select Edit/Preferences.