What is Web 2.0?

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Web 2.0 is a term originally coined by Tim O'Reilly in 2005 at a brainstorming session with MediaLive International. While the use of the term has blurred the actual meaning, Web 2.0 is really a set of practices and principles that can be visualized. Some of the basic principles that can be universally agreed upon are the cleaner, simpler designs, the proliferation of Ajax and the XMLHTTP Request object, and social applications, user contributions, and collaborations (all of which seemingly go hand-in-hand). Perhaps the easiest way to understand the concept of Web 2.0 is by example. The table below gives examples of the initial phase of the Internet or 'Web 1.0' and the equivalent from 'Web 2.0'. The image on the right gives a meme map with many of the original ideas and concepts of Web 2.0. Both figures are taken from O'Reilly's article titled What Is Web 2.0: Design Patterns and Business Models for the Next Generation of Software.