RSS (Really Simple Syndication) is a family of Web
feed formats used to publish frequently updated
content such as blog entries, news headlines or
podcasts. An RSS document, which is called a
"feed," "web feed," or "channel," contains either a
summary of content from an associated web site or
the full text. RSS makes it possible for people to
keep up with their favorite web sites in an
automated manner that's easier than checking
them manually.
RSS content can be read using software called an
"RSS reader", "feed reader" or an "aggregator". The
user subscribes to a feed by entering the feed's
link into the reader or by clicking an RSS icon in a
browser that initiates the subscription process. The
reader checks the user's subscribed feeds
regularly for new content, downloading any updates
that it finds. From Wikipedia