RSS (Really Simple Syndication) allows users to subscribe to frequently updated content like news headlines, blog posts, videos and more. When a user subscribes to an RSS feed, all new content is automatically delivered to their feed reader without needing to visit all the individual sites. Popular feed readers include Bloglines, iGoogle and NetVibes where users can organize all their feeds in one place. Many websites publish RSS feeds that users can subscribe to in order to keep up with regular updates.