The FOAF (“Friend of a Friend”) project is a community driven effort to define an RDF vocabulary for expressing metadata about people, and their interests, relationships and activities. Founded by Dan Brickley and Libby Miller, FOAF is an open community-lead initiative which is tackling head-on the wider Semantic Web goal of creating a machine processable web of data. Achieving this goal quickly requires a network-effect that will rapidly yield a mass of data. Network effects mean people. It seems a fairly safe bet that any early Semantic Web successes are going to be riding on the back of people-centric applications. Indeed, arguably everything interesting that we might want to describe on the Semantic Web was created by or involves people in some form or another. And FOAF is all about people. read the article on XML.com