Extracted from Sep 30, 2005 article by Terry O'Reilly entitled What is Web 2.0?

In exploring the seven principles above, we've highlighted some of the principal features of Web 2.0. Each of the examples we've explored demonstrates one or more of those key principles, but may miss others. Let's close, therefore, by summarizing what we believe to be the core competencies of Web 2.0 companies: 

1 Services, not packaged software, with cost-effective scalability 

2 Control over unique, hard-to-recreate data sources that get richer as more people use them 

3 Trusting users as co-developers 

4 Harnessing collective intelligence

5Leveraging the long tail through customer self-service

6 Software above the level of a single device 

7 Lightweight user interfaces, development models, AND business models

The next time a company claims that it's "Web 2.0," test their features against the list above. The more points they score, the more they are worthy of the name. Remember, though, that excellence in one area may be more telling than some small steps in all seven.

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