RSS 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 a "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.org
