Web 2.0 is the shift of the internet from a static information resource to a dynamic platform for user participation and interaction. Web 2.0 is not simply accessing information but interacting with it, developing, discussing, collaborating and sharing.
The web has gone from a read only platform to a read-write interactive experience. It is the Hub of a collective intelligence. The above diagram shows the comparison of web 1.0 and web 2.0 and the level of user participation in each phase.
Things such as blogs, social media and RSS are all part of web 2.0. It is not a specific technology but rather a platform of user interaction. The image shows just a few of the ever multiplying sites designed for and enabled by the concept of web 2.0.
User participation is the key of web 2.0. The above diagram lists other aspects and benefits of Web 2.0
[All images are screen grabs from the week 1 lecture published by UWS. Here is a summarisation of that lecture. https://idlnotation.wordpress.com/lectures-2/week-1-web-2-0-and-convergence/ ]
here is a useful link for understanding web 2.0 – webopedia – http://www.webopedia.com/TERM/W/Web_2_point_0.html