RSS stands for "Really Simple Syndication" or "Rich Site Summary" and is a system for creating news feeds from specific sites. A news feed includes headlines and links for the latest stories, updates and/or comments from a news sites and blogs.
To read an RSS feed, you need an RSS aggregator or reader. Many sites offer free readers -- such as
Bloglines or
Google Reader. The news reader is like your email inbox, but it only includes messages from feeds that you request: no spam.