I realize you can just as easily go to wikipedia and get this info yourself but, I am going to bring it to you anyhow!

The Semantic Web is a project to create a universal medium for information exchange by putting documents with computer-processable meaning (semantics) on the World Wide Web. Currently under the direction of the Web’s creator, Tim Berners-Lee of the World Wide Web Consortium, the Semantic Web extends the Web through the use of standards, markup languages and related processing tools.

Tags: Semantic Web, Markup Language, WWW, Tim Berners Lee, W3C