RSS is a family of Extensible Markup Language, or XML, for Web syndication used by (among other things) news websites and weblogs. The abbreviation refers to Really Simple Syndication. The technology of RSS allows Internet users to subscribe to websites that have provided RSS syndication, or "feeds". These are typically sites, like blogs and wikis, which change or add content regularly. The RSS formats provide web content or summaries of web content together with links to the full versions of the content and other metadata. Unlike subscriptions to many printed newspapers and magazines, RSS subscriptions are free.
In addition to facilitating syndication, RSS allows a website's frequent readers to track updates on the site using an aggregator. An aggregator is a software application that is able to subscribe to a feed, check for new content at user-determined intervals, and retrieve the content.