Web 2.0 is the term given to the new wave of Rich internet Applications that emphasize online collaboration and sharing among users. These web based applications are broad and varied, ranging from fun to more useful personal productivity tools to serious Office Applications.

Was there a Web 1.0? Every industry has its evolutionary stages and so does the IT industry. In the emerging phases of the Web in 1994, the Dot Com boom as it is now known; people felt that reaching the masses was easy and quick as a thought. Everyone was working towards a global village. The gold rush to the Internet spawned numerous companies. Funding houses were commonplace and everyone who had some kind of service to provide wanted to get online.

In 2001, the Dot Com bubble burst. Venture Capitalists disappeared and so did the startups. The IT industry went down along with the stock market.

The subsequent entrepreneurs of the resurgent Internet economy were more careful and started on a conservative scale. They based their models on need and this is crucial to driving mass uptake of any product or service. Technology was the foundation of their products and they ensured that the service functioned smoothly, and quickly. Unnecessary frills were avoided and faster technologies and client side scripting were used generously.

Users have options to use these sites for social networking, community bonding, personal use, increase productivity of home based or small and medium businesses and even collaborating with friends and office colleagues. Quite a few of these services/applications are free to use resulting in mass adoption of these applications.

Web 2.0 can be called the second generation of websites that meet a requirement rather than try to create a requirement after creating a product. They tap the needs of groups of people with similar or dissimilar interests and ensure heavy user participation.

These sites cover a wide range of social networking sites, Collaboration, bookmarking sites, Start pages, mashups, Feed Trackers, wikis, web office and communication tools, data and media sharing sites, and folksonomies.

Tim O'Reilly of O'Reilly Media defines Web 2.0 as:

"Web 2.0 is the business revolution in the computer industry caused by the move to the internet as platform, and an attempt to understand the rules for success on that new platform. Chief among those rules is this: Build applications that harness network effects to get better the more people use them."