Carry posted a great entry on terminology. One of the concepts she mentioned is Web2.0. Now, I'm not saying I have a better definition of the term, but I have my own opinion, which is basically what everyone has only they try to look smart by referring to it as if its a well known, well defined, technical term. Bull. (well, maybe except 
Tim O'Reilly, who probably coined the term. He's also the one who invented 
LAMP).
Web2.0 is not about technology. Its about people, and the interaction between them. In a broader perspective, its about 
division of labour. Of course, having the right technology helps, but most of it is already out there.
It started with 
friendster,  
Orkut and the like. Those got boring after a while, but the ideas caught. Then came 
del.icio.us and 
technorati,  with the whole 
tagging thing. 
flickr also tagged along (>cough< sorry. couldn't help myself). The technology is trivial. The idea is radical. Its about breaking down hierarcies of knowlege and consequently distributing the ownership of knowledge. Hence 
folksonomy. (noticed that all my references are 
wikipedia? Did I say breaking down of hierarchies? Distributed ownership of knowledge?) And if knowledge is power, and it is, then we're talking about a break down of social hierarcies and distribution of socio-economic-political power. We're talking revolution, yeah. But seriously, remember the 
semantic web? You know why it would never work? Ontologies. Someone has to have the authority to dictate them. Well, ain't that kind of world no more, so we're tagging, and happy with that, thank you.
Oh, and of course - bolgs and 
RSS / 
ATOM syndication. Wouldn't have technorati without them. Again, the technology varies, but the idea stays the same. I call it 
ssammedia, which is mass media with the mass going the other way. Actual, that's probably where it started. After all, web2.0 is all about participation.
Now the big guys are picking up on it. Yahoo! with it's 
360 Google buying around. I'm sure MicroSoft will have a go, I've heard they already have something, but this is really against their grain.
The thing is, the technology is simple - simple to create and simple to use. Its the change of mindset that's interesting.
But still, where does 
AJAX fit in? Oh, it just does the same stuff but 
soo coool. Interestingly, where AJAX defines one style of web2.0 applications, there's also an 
alternative one.