Watch this: LOD - linking open data.

This article discusses the types of documents that can be found on the Internet and the use of Resource Description Framework (RDF) to enhance them. Most documents on the Web are hyper text markup language (HTML) documents, but there are also many documents that are based on Extensible Markup Language (XML) that provides a more structured document with more information. The RDF documents are mostly designed for machine processing, but there is a version called the RDFa which bridges both the human and data webs. The article also presents an example of an RDFa document.