The Resource Description Framework RDF allows you to describe web documents and resources from the real world—people, organisations, things—in a computer-processable way. Publishing such descriptions on the web creates the semantic web. URIs are very important as the link between RDF and the web. This article presents guidelines for their effective use.
J. Lehmann, and L. Bühmann. Proceedings of the 9th International Semantic Web Conference (ISWC2010), volume 6497 of Lecture Notes in Computer Science, page 177--193. Berlin/Heidelberg, Springer, (2010)