Facebook like button

The Facebook like button is a feature on the social networking website Facebook that is also a share icon. As a web bug, the Facebook like button reports to Facebook whenever a user visits a page containing a like button and uses those reports to compile records of what websites people visit.

It was first activated on February 9, 2009. On February 24, 2016, Facebook added new reactions that comprised Like, Love, Wow, Haha, Sad and Angry.

The like button is a feature of social networking service Facebook, where users can like content such as status updates, comments, photos, links shared by friends, and advertisements. The feature was activated February 9, 2009. It is also a feature of the Facebook Platform that enables participating websites to display a button which enable sharing the site's content with friends. When a user clicks the Like button, the content appears in the News Feeds of that user's friends. The button also displays the number of users that liked each piece of content, and may show a full or partial list of those users. This feature may appear differently on mobile web applications. A "Like Box" also allows Facebook page owners to see how many users and which of their friends like the page. The ability to like users' comments was added in June 2010.

Facebook describes "liking" as a way for users to "give positive feedback and connect with things [they] care about."

A lawsuit was filed in Los Angeles in 2010 claiming that Facebook should not allow minors to "like" advertising. Facebook said the suit was "completely without merit."

The Like button is one of Facebook's social plug-ins, which are for use on websites outside Facebook, a feature which launched 21 April 2010, as part of Facebook's Open Graph, an interface for integrating websites with Facebook's social graph. Speaking at Facebook's F8 developer conference on the day of the launch CEO Mark Zuckerberg said, "we are building a Web where the default is social".

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Wikipedia