Like button

A like button, like option, or recommend button is a feature in communication software such as social networking services, Internet forums, news websites and blogs where the user can express that they like, enjoy or support certain content. Like is the lowest level category feedback on content that a user can provide in internet based social networks, and it has positive impact as it indicates that the user found the content interesting, useful or worth considering . Internet services that feature like buttons usually display the number of users who liked each content, and may show a full or partial list of them. This is a quantitative alternative to other methods of expressing reaction to content, like writing a reply text. Some websites also include a dislike button, so the user can either vote in favour, against or neutrally. Other websites include more complex Web content voting systems, for example five stars.

The like button was first announced as a FriendFeed feature on October 30, 2007 and was popularized within that community. Later the feature was integrated into Facebook before FriendFeed was acquired by Facebook August 10, 2009.

The Facebook like button is designed as a hand giving "thumbs up". It was originally discussed to have been a star or a plus sign, and during development the feature was referred to as "awesome" instead of "like". It was introduced on 9 February 2009.

In 2010, as part of a wider redesign of the service, YouTube switched from a star-based rating system to Like/Dislike buttons. Under the previous system, users could rate videos on a scale from 1 to 5 stars; YouTube staff argued that this change reflected common usage of the system, as 2-, 3-, and 4-star ratings were not used as often.

In 2012, YouTube briefly experimented with replacing the Like and Dislike buttons with a Google+ +1 button.

Google has a like button called the +1. +1 was introduced in June 2011. In August 2011 the +1 button also became a share icon.

Instagram has a like button. It is a heart symbol similar to those in Twitter, Tumblr and VK. On the mobile app, double-tapping a photo also acts as a like button.

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