RSS (an abbreviation for Really Simple Syndication) is a web feed format used to publish frequently updated works—such as blog entries, news headlines, audio, and video—in a standardized format. An RSS document is usually called a "feed" and includes summarized text, plus data such as publishing dates and authorship.

Web feeds are a means to syndicate content automatically. RSS feeds can be read using software called an "RSS reader", "feed reader", or "aggregator", which can be web-based, desktop-based, or mobile-device-based. A standardized XML file format allows the information to be published once and viewed by many different programs. The user subscribes to a feed by entering the feed's URL into the reader or by clicking an RSS icon in a browser that initiates the subscription process. The RSS reader checks the user's subscribed feeds regularly for new work, downloads any updates that it finds, and provides a user interface to monitor and read the feeds.