A primary use of feeds is to allow you as an end user to keep up with lots of information from many different sources—all in one place. News aggregators (also known as feed readers) gather items from the feeds you subscribe to and present them to you to read in a single interface.

Subscribing to feeds has become such a sufficiently mainstream activity for web users that modern web browsers now provide options for doing so when the user arrives at an RSS or Atom feed in the browser. For example, in Firefox 2.0+, you see options for how to subscribe to that feed, as shown in Figure 4-2.

Figure 4.2. Figure 4-2.Choosing a news aggregator with which to subscribe to a feed in Firefox