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The term "Web 2.0" began to gain popularity after O'Reilly Media hosted the Web 2.0 Conference in 2004. Web 2.0 moves away from the conventional notion of centralized websites and focuses on shifting "power" to desktops/mobile devices. One commonly cited example is Encyclopedia Britannica vs Wikipedia. Encyclopedia Britannica represents the old paradigm, where only experts are allowed to author articles which are released to the consumers in subsequent updates. Wikipedia, on the other hand, relies on the contributions of everyday users.
Examples of Web 2.0 tools include RSS feeds and tagging. RSS feeds allow users to recieve updates from websites. Moreover, these updates can be narrowed by keywords or content to specifically tailor to the user. Tagging helps sort and classify information, which helps develop communities of like-minded users.
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