What Is Web 2.0
Design Patterns and Business Models for the Next Generation of Software
by Tim O'Reilly
http://www.oreillynet.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web-20.html?page=1

Quote:
Core Competencies of Web 2.0 Companies
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:
* Services, not packaged software, with cost-effective scalability
* Control over unique, hard-to-recreate data sources that get richer as more people use them
* Trusting users as co-developers
* Harnessing collective intelligence
* Leveraging the long tail through customer self-service
* Software above the level of a single device
* Lightweight user interfaces, development models, AND business models

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