Web 2.0

Web 2.0 is a “perceived” second-generation of Web based communities and hosted services, such as social networking sites, wikis, blogs, mashups and folksonomies.

In the opening talk of the first Web 2.0 conference, Tim O'Reilly and John Battelle summarized what they saw as the themes of Web 2.0. They argued that the web had become a platform, with software above the level of a single device, leveraging the power of the "Long Tail", and with data as a driving force. According to O'Reilly and Battelle, an architecture of participation where users can contribute website content creates network effects. Web 2.0 technologies tend to foster innovation in the assembly of systems and sites composed by pulling together features from distributed, independent developers. (This could be seen as a kind of "open source" or possible "Agile" development process, consistent with an end to the traditional software adoption cycle, typified by the so-called "perpetual beta".)