Facebook said today that "Reactions", an extension of the "Like" button, was now available worldwide.

The social network launched a pilot of "Reactions" - which allow users able select from seven emotions including "like" and "wow" - in Ireland and Spain in October.

To add a reaction, users have to hold down the "Like" button on mobile devices or hover over the button on desktops to see a menu of reaction images, Facebook said in a blog post.