What are feeds?
Feeds are an easy way of keeping up to date with changes to a website without having to repeatedly visit that website. You can subscribe to an RSS feed using a piece of software called a Feed Reader. The Feed Reader will keep an eye on the feeds you've subscribed to and will show you any new content, a lot like an email program monitors your email account and lets you know when you've got new messages.
You can find more information on RSS feeds and links to feed reader software on the What is RSS website.