RSS stands for either Rich Site Summary or Really Simple Syndication, either way it refers to the same technology that delivers updated information through the means of subscription. It is especially popular to view news headlines, blog entries and other regularly updated materials quickly.
What's the difference?
There are different versions of RSS and different names sometimes, the most common version is RSS 2.0 and the newest member is called Atom, RSS 2.0 is the most commonly used version.
How to Read RSS?
Each individual RSS is called a FEED, and these feeds are updated on regular basis. You can subscribe to a feed by using a program called an RSS aggregator, RSS aggregators can read RSS feeds like email programs would read emails.