Web 2.0

Web 2.0, also called Internet 2.0, refers to a set of collaborative online technologies and services that proliferated rapidly starting in the mid-2000s. This proliferation resulted in an explosion of user-generated content freely available online. Individuals and organizations around the world have made enthusiastic and innovative use of Web 2.0 tools, for social, cultural, economic, and political purposes. However, critics of Web 2.0 point to a proliferation of low-quality content, a loss of privacy, an increased capacity of states to monitor their citizens' behavior, and a degeneration of the term itself into a marketing buzzword.

The term Web 2.0 was coined in 2004 by publisher Tim O'Reilly. Web 2.0 encompasses a group of design principles and business models underpinning companies, services, and websites that emerged after the bursting of the dot-com boom in 2000.

One design principle is that the application or service runs on the web and is accessed through a web browser, rather than being a stand-alone application running on a particular operating system. This allows access to the service regardless of the user's device (e.g., Windows PC, Mac, smart-phone). The user can benefit from the latest version of the service without having to upgrade any software on his or her device.

A second principle is that data management—the rapid and reliable gathering, storage, linking, and retrieval of information—is central to any Web 2.0 service. There is no limit to the amount of information a service can process; indeed, the more information a service contains, the more valuable it becomes to users. Information of interest only to a niche audience can be accommodated, allowing benefit and profit to be obtained from the “long tail” of less popular content. This requirement for infinite information capacity means that both software and hardware must be scalable. Google, a quintessential Web 2.0 company, early established a system for seamlessly adding data processing and storage capacity to its system. Other companies such as Amazon have capitalized on their huge investments in computing capacity by selling excess server capacity, thereby further reducing the startup and running costs for other Web 2.0 services.

A third principle is that a Web 2.0 service harnesses the collective intelligence of its users. Wikipedia, the free online encyclopedia, and YouTube, the video upload site, do this directly, making it as easy as possible for users to create and edit articles or upload videos. Millions of people publish their emotions or opinions on Twitter or myriad blogs. [Page 1782]Flickr, the photo-sharing site, not only invites users to post their photos but encourages other users to tag those photos, which then allows still other users to find images representing any object or concept. Amazon competes against other online and offline booksellers by offering reviews, ratings, and lists contributed by users and by giving prominence to titles bought by other users. Google's search engine algorithm employs collective intelligence more indirectly, by analyzing the links between webpages to establish which pages are likely to be of interest. Of course, much of the content generated through Web 2.0 services is produced by nonprofessionals and published without any quality controls; the Web 2.0 model is that good content becomes more visible as other users link to it or tag it and that bad content becomes better as other users edit it.

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