RSS is basically a way of reading the internet without really having to look at it. Think of all the sites that you hit every day to check for updates - if you sign up to an RSS feed, you can get all the updates sent to you, so you only need to load the pages when there's something new.

They're sort of like e-mails/newsgroup posts, only HTML formatted, etc. They're particularly useful for intermittently updated things like blogs or comics, or for things updated daily with lots of content, not all of which you're interested in - that way you can just pick out the stories that interest you.

I keep track of various blogs, comics and news sites (avoid monsters like BBC News or The Guardian, they take too much time), as well as things like MacUpdate and local Small Ads. Very useful indeed.

Download NetNewsWire (you are a Maccite, yes?) and have a go. You'll find yourself spending so much less time browsing the net (but consuming the same content) that you'll just sit in front of your computer feeling lost for the first week or so.

I sync it with NewsGator Online (which isn't great, but good enough) so I can keep track of all my feeds at work, then when I get home it knows what I've read. I can also flag things (like apps from my MacUpdate feed - BetterZip update today!) to be highlighted when I get home.

Sounds confusing at first, but it genuinely is Really Simple Syndication, and it's massively useful.