 Web 2.0 does not refer to an update to any technical specification, but rather to cumulative changes in the way Web pages are made and used.Web 2.0 describes an approach, in which sites focus substantially upon allowing users to interact and collaborate with each other in a social media dialogue as creators of user-generated content in a virtual community, in contrast to Web sites where people are limited to the passive viewing of content.Examples of Web 2.0 include social networking sites, blogs, wikis, folksonomies, video sharing sites, hosted services, Web applications, and mashups.