Every one of our article posts has been categorised by the writer in two different ways. First, the post is linked to the section of the newspaper that it relates to. The front page of the site has links to the archives of these sections. This is simple.
The second way, however, is more involved. The writer adds keywords to each post to more finely describe the subject matter. These are called 'tags'.
We're not the only people to use tags. Del.icio.us and Flickr are the most notable, and well worth exploring.