Facebook like button years of questions from the public about whether it had an intention to incorporate a "Dislike" button, Facebook officially rolled out "Reactions" to users worldwide on February 24, 2016, letting users long-press on the like button for an option to use one of five pre-defined emotions, including "Love", "Haha", "Wow", "Sad", or "Angry". Reactions were also extended to comments in May 2017. The like button is one of Facebook's social plug-ins, in which the button can be placed on third-party websites. Its use centers around a form of an advertising network, in which it gathers information about which users visit
Criticism of Facebook "instant personalization". They demonstrated that anyone could get access to information saved to a Facebook profile, even if the information was not intended to be made public. A "connection" is created when a user clicks a "Like" button for a product or service, either on Facebook itself or an external site. Facebook treats such relationships as public information, and the user's identity may be displayed on the Facebook page of the product or service. Instant Personalization was a pilot program which shared Facebook account information with affiliated sites, such as sharing a user's list of "liked" bands with a music