The Web 2.0 describes web sites that use technology beyond the static pages of earlier web sites. The characteristics of Web 2.0 are: rich user experience, user participation, dynamic content, metadata, web standards, and scalability. Further characteristics, such as openness, freedom and collective intelligence by way of user participation, can also be viewed as essential attributes of Web 2.0. The Web 2.0 is possible thanks to the advances of distributed systems and applications construction, and to fundamental concepts that remain important to understand, the current state and evolution of the Web as a technological platform.