How Semantic Web Works – The World Wide Web is an interesting paradox — it’s made with computers but for people. The sites you visit every day use natural language, images and page layout to present information in a way that’s easy for you to understand. Even though they are central to creating and maintaining the Web, the computers themselves really can’t make sense of all this information. They can’t read, see relationships or make decisions like you can.The Semantic Web proposes to help computers “read” and use the Web. The big idea is pretty simple — metadata added to Web pages can make the existing World Wide Web machine readable. This won’t bestow artificial intelligence or make computers self-aware, but it will give machines tools to find, exchange and, to a limited extent, interpret information. It’s an extension of, not a replacement for, the World Wide Web.

This article discusses what you need to know to make your Web site part of the Semantic Web. It starts with a discussion of the problems the Semantic Web tries to solve and then moves to the technologies involved, such as Resource Description Framework (RDF), Web Ontology Language (OWL), and SPARQL Protocol and RDF Query Language (SPARQL). You’ll see how the Semantic Web is layered on top of the existing Web. It then covers some issues that you want to know about when you plan a new Web site and also gives specific examples of how to use technologies like RDFa and Microformats to enable your existing Web site to become a part of the Semantic Web.

Piggy Bank is a Firefox extension that turns your browser into a mashup platform, by allowing you to extract data from different web sites and mix them together.
Piggy Bank also allows you to store this extracted information locally for you to search later and to exchange at need the collected information with others.