The anatomy of web 2.0: The web as a platform to promote users' participation and collaboration

In the last 20 years we have assisted to the birth and growth of the World Wide Web. It rapidly changed from a tool conceived for scientists at CERN, into a global information network, populated by billions of users. Currently, we are experiencing another change within the Web paradigm, where the Web is viewed as a read/write tool enhancing users' collaboration and participation in information creation, consuming and sharing. Web 2.0, intended as a second step in the Web's evolution, is a complex topic and therefore it is difficult to clearly define it. It concerns viewing the Web as a platform for the develop-ment of Rich Internet Applications that go beyond the page metaphor of Web 1.0. It lies on the ideas of 1) users' participation; 2) users production of content and; 3) data remixability, so that Web applications and services can be employed as social tools allowing mass users collaboration and information sharing. The authors describe in this chapter, the main concepts behind the Web 2.0 paradigm, together with the technological aspects and design patterns that demonstrate this new way to use and perceive the Web. In second stance, they highlight future directions and research trends which are leading to the next Web's evolution phase: the Social Semantic Web.