The Semantic Web
http://www.w3.org/People/Berners-Lee/
The Semantic Web is an extension to the current World Wide Web, which aims to allow computers, rather than only humans, to use the web effectively, in a universally accessible platform. This is accomplished by giving meaning to data on the web. If we can design common languages and formats for data, we can draw data from multiple different sources, allowing a person or machine to travel through a never-ending series of databases, all joined by common subjects and ideas - we would be able to search for data, rather than simply the documents containing this data. It derives from Tim Berners-Lee's vision of the Web as a universal medium for data, information, and knowledge exchange.
In the future, it is conceivable that not just web pages, but databases, programs, sensors, personal devices (e.g. mobile phones and PDAs), and even household appliances like cookers and microwaves, could be able to use and produce data on the internet. Software agents would be able to use this data to search and organise information in various different ways, allowing many of the tasks that take us so much time to be performed automatically and on the fly.
But it's not just about searching for the information we know we want. With the Semantic Web we could draw research, information and ideas from all different fields, and make new discoveries based on this data. We would no longer be limited by the knowledge of the researcher, or their perceptions of what they thought might be useful. Researchers in all different areas could work in parallel, making breakthroughs that span all the traditional 'departments' of science.
Further applications could even include e-learning systems, personalized newspapers and journals, intelligent devices, and so on.