Web 2.0

Web 2.0 is a term for the stage of the web, from about the mid-2000s, in which users create and share much of the content, rather than only reading pages. The phrase was used as early as 1999 and popularised by a 2004 conference run by the publisher Tim O'Reilly. It covers blogs, wikis, video sharing, social networks, online marketplaces and smartphone apps. Technically it was driven by richer web applications, open APIs and cloud hosting. Commercially it rewarded platform companies that attract huge audiences and earn money mainly from advertising and data. Critics point to the concentration of power and the trade-offs for data privacy this created. Those concerns inspired Web3, which promises user ownership through blockchains; see also Web 1.0.