What is Web 2.0?

Web 2.0 is an undefined buzzword used to describe websites utilizing technologies and techniques not common, or not available, in early websites. Typically, Web 2.0 applications are written in accessible, open formats such as XML and present the user with simple, easy to understand page components. Advanced communication techniques such as Ajax enable user-interaction in real time, greatly improving website responsiveness and enabling features undreamed of in the design of the World Wide Web. As the term Web 2.0 has no formal definition, the decision whether or not any particular website is 2.0 is subjective and open to debate. Thus, the term is more of a marketing buzzword than a description of any advanced technology. The most common applications of Web 2.0 techniques are seen in the social networking sector including wikis, blogs, personal homepages, and public bookmarking services.

From a design perspective, Web 2.0 websites usually make a clear distinction between website interface, navigation, page content, and advertising. Headers, footers, are other interface components are typically lightly-colored and have clear boundaries. Navigational elements of Web 2.0 sites are usually, but not always, presented as tabs below the header, and the tab corresponding to the active content is distinct from the other tabs. These and other navigational elements are often brightly-colored and react to mouse position. The textual content of Web 2.0 pages is expected to be of a much larger font than the text of the early Word Wide Web, and is usually coded in such a way as to respect the users' choice of font size in his web browser. Although early Web 2.0 applications had advertisements clearly separated from the page content, more recent examples have seen the advertisements mixed in with the text. While in principal this is against the Web 2.0 ideology of simplicity and separation of components, it seems that this technique is the only way to force users to click on advertisements. While many users and designers feel that this may be unethical, the World Wide Web, like the real world, is driven by money.

From a technological perspective, Web 2.0 websites tend to provide standards-compliant code using presentation technologies not available in the early years of the World Wide Web. HTML is giving way to XHTML, and CSS is separating content from presentation. This enables Web 2.0 websites to present their content in many different formats and specialized interfaces for varying applications. Stand web browsers may be served standard webpages, and other devices such as PDA's and cellphones may be served pages specifically tuned for that device. RSS feeds can be used to inform users of new content, and overall semantic markup makes the use of screen readers and other non-conventional devices possible. Although most Web 2.0 applications are delivered in code that does conform to the latest standards, very few Web 2.0 applications have alternative interfaces that work in older, less advanced web browsers. This is ironic as the separation of content and presentation makes the design of these alternative interfaces trivial.