Facebook said on Wednesday that "Reactions", an extension of the "Like" button, has now been rolled out worldwide.

The social network launched a pilot of "Reactions" - which allows users to select from seven emotions including "Angry", "Sad" and "Wow" - in Ireland and Spain in October.

In a video accompanying a blog post, the five new buttons appear as animated emoticons that pop up when the "Like" button is held down on mobile devices. The buttons appear on desktops when users hover over the "Like" button.

Today we’re launching a pilot test of Reactions — a more expressive Like button. As you can see, it’s not a “dislike”...

Posted by Chris Cox on Thursday, October 8, 2015

"We will initially use any Reaction similar to a Like to infer that you want to see more of that type of content," Facebook said in separate blog post.

The company said that over time it hoped to learn how different "Reactions" should be weighted differently by the Facebook News Feed to customize it for individual users.

Facebook said "Reactions" would have the same impact on ad delivery as "likes".