Web 2.0 is a trend in the use of World Wide Web technology and web design that aims to facilitate creativity, information sharing, and, most notably, collaboration among users. (Link to a Short summary)
Why the Web 3.0 Matters and you should know about it
From the O'Reilly School of Technology
writes:
In our initial brainstorming, we formulated our sense of Web 2.0 by example:
Web 1.0 | Web 2.0 | |
---|---|---|
DoubleClick | --> | Google AdSense |
Ofoto | --> | Flickr |
Akamai | --> | BitTorrent |
mp3.com | --> | Napster |
Britannica Online | --> | Wikipedia |
personal websites | --> | blogging |
evite | --> | upcoming.org and EVDB |
domain name speculation | --> | search engine optimization |
page views | --> | cost per click |
screen scraping | --> | web services |
publishing | --> | participation |
content management systems | --> | wikis |
directories (taxonomy) | --> | tagging ("folksonomy") |
stickiness | --> | syndication |
Like many important concepts, Web 2.0 doesn't have a hard boundary, but rather, a gravitational core. You can visualize Web 2.0 as 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.
Figure 1 shows a "meme map" of Web 2.0 that was developed at a brainstorming session during FOO Camp, a conference at O'Reilly Media. It's very much a work in progress, but shows the many ideas that radiate out from the Web 2.0 core.