In Software engineering we distinguish between different software versions by giving them a number such as v1.0, v1.1, v2.0 and so on and so forth.
BUT when you say web 2.0, it doesn’t mean that it’s another version of World Wide Web. This is a common misconception people are having nowadays.
Web 2.0 is a term used by Tim O’Reilly, to explain a new era of the world wide web after the dot com crash (dot com bubble burst). But it cannot be consider as a newer “Version” as in Software Engineering. Though it seems like a new version, web 2.0 is just the set of new technologies used in the existing web in order to collaborate.
Some people use the term web 2.0 as a Marketing term in order to market their products and services.
According to O’Reilly Net, Web 2.0 is a “set of principles and practices that tie together a veritable solar system of sites that demonstrate some or all of those principles, at a varying distance from that core”
For me, Web 2.0 is a platform of new technologies used in cyber space in order to achieve a more collaborative nature between the users, where users are the creators/ authors of the content published in the World Wide Web.
Below figure shows the distinguish nature between the technologies in web 1.0 Vs. web 2.0
[Image source: O’ReillyNet, 2005, viewed on 31st August 2008]
So as you can see from the above image, AdSense, WordPress/ Google Blogs, Social networks such as FaceBook/ ElaKiri.com, Wikis are good examples of web 2.0 technologies.