Excellent RSS Tutorial
From What is RSS:
"RSS allows you to receive notification of current content without having to visit the web site of interest to determine if it has been updated. This is powerful stuff, since it means that with the right tools you can monitor a large number of sites in a relatively short period of time.
RSS became popular with the growth of blogs as a way for people to keep up with their favs. But it is being used increasingly by a variety of websites including those with commercial news content. For the researcher that's what makes it so useful. More and more valuable content is becoming available via RSS everyday. Anyone who needs to monitor current news on a regular basis will need to understand and use RSS in some form going forward."