The name Atom applies to a pair of related standards. The Atom Syndication Format is an
XML language used for
web feeds, while the Atom Publishing Protocol (APP is the acronym, but it is referred to as 'AtomPub' for short) is a simple
HTTP-based protocol for creating and updating Web resources. Web feeds allow
software programs to check for updates published on a web site. To provide a web feed, a site owner may use specialized software (such as a
content management system) that publishes a list (or "feed") of recent articles or content in a standardized, machine-readable format. The feed can then be downloaded by web sites that syndicate content from the feed, or by
feed reader programs that allow Internet users to subscribe to feeds and view their content.
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