About RSS
RSS commonly stands for "Really Simple Syndication" and is an XML data format for syndicating or feeding data without user intervention.
Think of it as a news ticker that updates itself over the web. In other words, you have a one-stop syndication source for all the web publications you care about!
Many RSS feeds are available around the web - from major news outlets, magazines, retailers, blogs, and more.
You can read more about RSS at Wikipedia.
Some Common RSS Feed Readers
Many modern web browsers, like Firefox, Safari, and Opera have built-in feed reading capabilities. With it's latest 7.0 release, Microsoft's Internet Explorer has caught up with the pack.
There are also a number of applications specifically designed to aggregate RSS feeds (and other syndication technologies, like Atom) such as RSS Owl, which is available for all major operating systems.
Finally, many customizable homepage portals like iGoogle and NetVibes feature built-in support for RSS feeds, so you can read your favorite news on your homepage!