What is RSS?
RSS (RDF Site Summary or Really Simple Syndication) is a language a website can use to produce summaries of its recently updated content in a form which personal news readers and other websites can republish. RSS feeds allow users to read headlines from many different websites at once. Instead of repeatedly checking your favorite sites, you can check your news aggregator service in a web browser or through an email client. From your web-based or desktop news aggregator you will see latest headlines and teasers from feeds to which you subscribe. These headlines are linked to corresponding content on the original website that produced it.
Think of it this way – instead of going to websites to see what is new, subscribe to their feeds and receive the updates like you receive email, either to a web-based aggregator (like web mail) or a desktop aggregator (like email with an email client, but easier to setup).