To learn more about ontologies on the semantic web,
The Web Ontology Language OWL is now a W3C Candidate Recommendation and is the undoubted champ when it comes to which ontology language to use. Check it out!
For the brave, an extended example from that article goes into
great detail about web markup and ontologies. Click
here to begin.
For those with less time to spend, a quick overview of that same
semantic web annotation can be found by clicking the icons on the
right-hand side of my home
page .