RSS allows you to subscribe to websites that have provided RSS feeds, typically sites that change or add content regularly (or in my case, not so regularly ) like daveryder.com does.
By subscribing to our RSS feed you will receive the latest Dave Ryder news as soon it is published (yay!).
In the typical scenario of using web feeds, a content provider (like me) publishes a feed link on their site which end users (you) can register with a feed reader. Readers can be scheduled to check for new content whenever you like.
Where can I get a Feed Reader?
Here is a list with comparison charts of most RSS Readers. I actually use the RSS Reader built into my email client (Thunderbird), so I really can’t recommend one.
Web feeds have some advantages compared to receiving frequently published content via email:
For a better explaination of RSS feeds go here.
Google answers these types of questions better than me