After more than a year in development, Facebook's expanded Like button "reactions" are now coming to a News Feed near you. For the first time, you'll be able to react to friends' posts with something other than a gesture of pure positivity. Long press on the Like button and you'll now see "love," "haha," "wow," "sad," and "angry," and posts will now show the mix of reactions they've received. And while there's no "dislike" button, as some users have long requested, Facebook says that the new mix of reactions has proven popular with users during testing in Spain and Ireland. It's launching today on iOS, Android, and the web.

The road to an expanded range of reactions began last year, when Facebook CEO Mark Zuckerberg told members of the News Feed team that the time had come to move beyond the simple Like. "Everyone's had one of these posts in News Feed where they're like, I want to respond in some way, but 'like' doesn't feel appropriate at all," says Tom Alison, director of engineering for the News Feed. To determine an initial set of new reactions, Facebook looked at the one-word comments people left the most on their friends' posts, as well as analyzing the sentiments in the most popular stickers posted as comments.

"It was really important to us that this was something that could be universal."

Testing in Spain and Ireland led to two reactions being trimmed from the initial list: "yay" and "confused." In both cases, users who posted the reaction once were unlikely to use it again. (One-time "yay" enthusiasts mostly gravitated toward "love," Alison says.) The new reactions are rolling out now because people in test countries all tended to use reactions similarly, giving Facebook's confidence that it could roll them out around the world without confusing people too much. "It was really important to us that this was something that could be universal," Alison says.

But even though new reactions are here, the Like retains its supremacy in Facebook's pecking order. When you scroll through your feed, it's still the Like button you see on every post — the rest are hidden beneath that long press. (On the desktop web, you can also access them by hovering over the Like button.) But to help you find the feature, Facebook will pop up a tip inside the app to show you how it works. People who tested the feature also found it because of the mix of icons that now appears below posts alongside likes. (Instead of telling you how many people liked something, Facebook now tells you how many people "reacted" — somewhat robotic language that was chosen for its simplicity, the company says.)

Notably, reactions will be available for both individual and business pages — meaning that if you want to angry-bomb a bad advertisement in your News Feed, there's nothing to prevent you from doing so. But Facebook says it will keep an eye on any misuse of reactions. So "haha" at the death of your friend's grandmother at your peril.

Given the emotional range of items people to post on Facebook, it's long since time that the Like button make room for some alternatives. Facebook's relative slowness in introducing them speaks to the supreme importance of the News Feed in the corporate hierarchy: it's the part of Facebook users see the most, and it's also where the company makes the bulk of its profits. People will quibble with the implementation, but on the whole it feels thoughtfully designed. Likeable, even.

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