Why RDF model is different from the XML model

This note is an attempt to answer the question, "Why should I use RDF - why not just XML?". This has been a question which has been around ever since RDF started. At the W3C Query Language workshop, there was a clear difference of view between those who wanted to query documents and those who wanted to extract the "meaning" in some form and query that. This is typical. I wrote this note in a frustrated attempt to explain whatthe RDF model was for those who though in terms of the XML model.

http://www.w3.org/DesignIssues/RDF-XML.html