What is Web 2.0
Web 2.0 is the term given to describe a second generation of the World Wide Web that is focused on the ability for people to collaborate and share information online. This term basically refers to the transition from static HTML pages to a more dynamic page that is more organized and is based on serving applications to users.
Other improved functionality includes open communication with an emphasis on Web-based communities of users, and more open sharing of information. Over time, the term has been used more as a marketing term than a computer-science-based term. Blogs, wikis, and Web services are all seen as components of Web 2.0.
Web 2.0 was previously used as a synonym for Semantic Web, but while the two are similar, they do not share precisely the same meaning.