The objective here is to inter-connect people with each other and their collective knowledge in meaningful ways. There is also the opportunity to visualise these relationships.
The semantic web was envisaged by Tim Berners-Lee in 1999 “I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web – the content, links, and transactions between people and computers. A ‘Semantic Web’, which should make this possible, has yet to emerge, but when it does, the day-to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines. The ‘intelligent agents’ people have touted for ages will finally materialize.”
Examples of open source semantic web applications: