Web 2.0 is a buzz phrase that has actually been around for a few years now. It was original coined to refer the next generation of the web. Presumably, Web 1.0 was all about static HTML pages. Web 2.0 was all about web applications. Then, with the advent of AJAX (Asynchronous JavaScript and XML), which is really more of a web development technique, and the trend to web application development grew quickly and the web moved to solidly to the next generation.

Although Web 2.0 has taken on some mixed meanings, it generally refers to the idea of applications residing on the web rather than locally on individual machines. Some of the more notable examples of this kind of web application are: Flickr, Del.icio.us, and Digg.