Web 3.0
After Web 2.0, it was thought that the next generation in Web technology would be the Semantic Web. The intent of the Semantic Web, as originally envisioned by Tim Berners-Lee, was to provide meaning, or semantics, to Web content, enabling programs on the Web to “read” and interact with this content in the same way as users (Target). Data exchange could be performed between programs without explicit programming or human intervention. The Semantic Web would therefore represent a “Global Brain” where content was processed by programs in the same way as human users, and the interconnected data that constitute the Semantic web would be understood both contextually and conceptually (Silver).
Semantics would be imparted to the Web through innovations in artificial intelligence (AI). AI has many different popular connotations, but in this case, it refers to any system, or intelligent agent, that receives input from its environment and executes actions to perform a task, or achieve a goal, based upon that input. These intelligent agents range from human beings to thermostats, to biomes. However, in the present context, intelligent agents refer to computational systems that implement AI through sensing or perceiving their environment.
American computer scientist and cognitive scientist John McCarthy (1927 – 2011), an early researcher in the field who coined the term “artificial intelligence” in 1956, defined it as follows (McCarthy, What is AI?, 2004):
Q. What is artificial intelligence?
A. It is the science and engineering of making intelligent machines, especially intelligent computer programs. It is related to the similar task of using computers to understand human intelligence, but AI does not have to confine itself to methods that are biologically observable.
Q. Yes, but what is intelligence?
A. Intelligence is the computational part of the ability to achieve goals in the world. Varying kinds and degrees of intelligence occur in people, many animals and some machines.
In the context of the Semantic Web, specialized programs – the intelligent agents – would automate the same types of tasks on the Web that are done by human users. The mechanism by which this could be done is through XML (Extensible Markup Language) on web pages. The XML would not affect the appearance of the web pages but would encode information that can be read by other programs on the web. This information, or metadata, would allow specialized web browsers respond to queries, utilizing a large number of webpages (Target).
There was a large amount of research and development activity on the Semantic web between 2001 and 2005. During this time The World Wide Web Consortium (W3C), a large, international forum for the proposal and development of Web standards, worked on many standards that were intended to bring the Semantic Web to realization. Arguably the most important standard was RDF, or Resource Description Framework, mentioned above in the context of RSS. RDF was to provi