While some are still struggling to figure out what Web 2.0 really means, there is already a buzz on Web 3.0. This was partly ignited by John Markoff's Nov. 12 article in the New York Times on a "web guided by common sense" where he described the future of the Web as one that makes use of artificial intelligence and common sense to provide highly intelligent responses and interactions. Interacting with Web 3.0 will be just like interacting with a human.
Is Web 2.0 already passé then, you might ask. Quite the contrary, Web 2.0 is even more important than ever before because Web 3.0 isn't quite here yet. In fact, the HAL-like abilities of Web 3.0 might not ever happen, at least not in the near future.
What is Web 3.0 then? Basically, it is a remarketing of the Semantic Web. Semantic Web is of course not new. Sir Tim Berners-Lee outlined his road map of the semantic Web back in 1998. Since then, progress has been made with the release of W3C recommendations such as the Resource Description Framework (RDF) and OWL Web Ontology Language (OWL) in early 2004. The idea is that in the future, all Web content and knowledge will be represented in RDF format using OWL as the terms or ontologies. Once contents are in the Semantic Web form, the Web becomes a gigantic AI knowledge base and software can make intelligent sense of contents and reason with them.
Some believe that the remarketing of the semantic Web as Web 3.0 is actually a bad idea. Tim O'Reilly, who created the term Web 2.0, believes Web 2.0 already covers a lot of ground promised by Web 3.0. Others see Web 2.0 and Web 3.0 as two different things. Web 2.0 is about human collaboration and collective intelligence. Web 3.0 is about software collaboration and intelligent search.
Although full-fledged Web 3.0 is still a faraway target, bits and pieces of Web 3.0 technology are gradually being integrated into Web 2.0. The most popular use of Semantic Web technology is probably the RDF Site Summary (RSS 1.0) feed format which is used for news/blog syndication. Another technology that uses Semantic Web is the Friend of a Friend (FOAF), which is a standard way to describe people, groups, companies, etc. and their relationships.
The key objective of Semantic Web is to create common syntax and common languages and vocabularies so that software can make sense of content from disparate sources. For example, RSS allows us to aggregate news from different blog sites and FOAF allows us to construct a social network from independent personal Web sites. But RDF and OWL are not the only technologies that can achieve the semantic Web vision.
Other technologies, such as microformats, also make it easier for different data sources to exchange information. The recent news of Yahoo! and Microsoft standardizing on the Google Sitemap Protocol is another example of moving towards the semantic Web vision.