RSS - Stands for Real Simple Syndication,

Makes information, through a 'subscription', available to other Websites or to individual subscribers. The bottom line: you don't have to go to different websites for information, you can design an RSS Reader/Aggregator so that the information that you want comes to you!

RSS Feeds in Plain English

RSS Readers

Google Reader

RSS for the classroom - good article
Here's an and a screencast about how to use RSS for yourself and its uses with your students. Pages 1-5 of the pdf article state in text format what you'll see in the screencast. From page 6 on it gives suggestions on how to use the feeds with student projects.