Facebook researchers started the project by compiling the most frequent responses people had to posts: “haha,” “LOL,” and “omg so funny” all went in the laughter category, for instance. Emojis with eyes that transformed into hearts, GIF animations with hearts beating out of chests, and “luv u” went in the love category. Then they boiled those categories into six common responses, which Facebook calls Reactions: angry, sad, wow, haha, yay, and love.
Facebook Reactions won’t get rid of like—it will be an extension. Within the company, there was some debate on how to add the options without making every post look crowded with things to click. The simpler Facebook is to use, the more people will use it. Zuckerberg had a solution: Just display the usual thumbs-up button under each post, but if someone on her smartphone presses down on it a little longer, the other options will reveal themselves. Cox’s team went with that and added animation to clarify their meaning, making the yellow emojis bounce and change expression. The angry one turns red, looking downward in rage, for example. Once people click their responses, the posts in News Feed show a tally of how many wows, hahas, and loves each generated.
edit: Yay was rejected as a choice.