Flickr

Flickr is a photo sharing website and web services suite, and an online community platform, which is generally considered an early example of a  Web 2.0 application.In addition to being a popular Web site for users to share personal photographs, the service is widely used by bloggers as a photo repository. Its popularity has been fueled by its innovative online community tools that allow photos to be tagged and browsed by folksonomic means.
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