Web 2.0 is a feature through which applications and services are made around the unique feature of Internet rather than making applications and expecting the Internet to be feature around it.

The technologies of Web 2.0 tend to bring the creative and innovative ideas and the features of different developers together. The hierarchy of Web technology 2.0 has 4 Levels. Each level has its different usage and advantages.

The applications that are only web based i.e. they work only when they are connected to the Internet. They are mainly in the Level 3 of Web 2.0. For example, websites like e-Bay, Skype, AdSense and many more than can only work when online.

There are certain features which are available in Web 2.0 which gives us the advantage of working offline also. These are mainly in the Level 1 and Level 2.

For example: Website like Flickr, ITunes which gives us the advantage of sharing music and photos on the net.

These websites can work without being connected to the Internet but once connected gives additional advantages like live photo sharing, music sharing and many more. Certain applications of Web 2.0 give us the feature of total offline working advantages. Websites like MapQuest, Google Maps and many more gives us this facility.

Web 2.0 has changed the scene of the World Wide Web. It allows the users to do more than just to retrieve data and information. It allows the user to rather own the data than to just retrieve it from the source. It also encourages the user to add values and information to the application which is in contrast to the old traditional websites which lets only the selected users to access the data and information and allows only the site Administrator to add or edit the data. Technologies such as weblogs, forums, podcasts, wikis, social software and web application programming Interfaces provide enhancement over read-only websites.

The idea of Web 2.0 can also relate to a transition of some websites from isolated information based applications to interlinked computing platforms that function like locally-available software in the view of the user. It also includes a social element where users generate and distribute content, often with freedom to share and re-use. This can even help in the rise of economic value of web to business, as users can perform many more activities online.

It has many more features like it is a rich user experience as it is developed on a rich user friendly interface like AJAX, FLEX or similar rich media. It gives user participation. It even gives open ness and freedom of use to all the users. By user participation it contributes to collective intelligence which helps the further user of the data.

Web 2.0 has prompted the developers to develop websites that mimic desktop applications such as word processing, the slide show presentation. AJAX has prompted certain developers to develop web based operating systems like EyeOS and YouOS. These services mimic the user experience of desktop Operating System that is similar to a Personal Computer environment. These Operating Systems has the ability to work within any modern browser. Some other of the Web based Operating System is WebEX.

Web 2.0 applications can be brought to the user by rich user friendly Internet Application techniques like Adobe Flash, Java, AJAX, Flex and many of such kind. These have the potential to improve the user-experience in browser-based applications. These technologies allow a web-page to request an update for some part of its content, and to alter that part in the browser, without needing to refresh the whole page at the same time.

The extra functionality provided by Web 2.0 depends on the ability of users to work with the data stored on servers. This can come about through forms in an HTML page, through a scripting-language such as Javascript / Ajax, or through Flash or Curl. These methods all make use of the client computer to reduce server workloads and to increase the responsiveness of the application.