RSS is a format for syndicating news and the content of news-like sites and personal weblogs. But it's not just for news. Pretty much anything that can be broken down into discrete items can be syndicated via RSS. Once information about each item is in RSS format, an RSS-aware program can check the feed for changes and react to the changes in an appropriate way.
RSS-aware programs called news aggregators are popular in the weblogging community. Many weblogs make content available in RSS. A news aggregator can help you keep up with all your favorite weblogs by checking their RSS feeds and displaying new items from each of them.
So, in other words, rather than logging into your favorite websites to keep up with the changes, why not let the changes come to you?
All you'll need is a news aggregator. One I like is SharpReader but there are a ton out there. You'll also need to know the URL for the feed you want to monitor. The Digital Dentist feed is right here or click Site Feed under Links.