TheGuardian.com, formerly known as Guardian.co.uk and Guardian Unlimited, is a British news and media website owned by the Guardian Media Group. It contains nearly all of the content of the newspapers The Guardian and The Observer, as well as a substantial body of web-only work produced by its own staff, including a rolling news service. As of November 2014, it was the second most popular online newspaper in the UK with over 17 million readers per month; with over 21 million monthly readers, Mail Online was the most popular.
The site is made up of a core news site, with niche sections and subsections covering subjects including sport, business, environment, technology, arts and media, and lifestyle. TheGuardian.com is notable for its engagement with readers, including long-running talkboards and, more recently, a network of weblogs. Its seven blogs were joined on March 14, 2006, by a new comment section, “Comment is free”, which has since merged into its Opinion section.
The site can be viewed without cost or registration, though some services such as leaving comments on articles require users to register. In March 2009, Guardian.co.uk launched their API, using the OAuth protocol and making a wide range of Guardian content available for use by web application developers.

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