When a card appears on our device, we’ll have the ability to swipe to the left and see some options for a reply, which Google calls action buttons. The easiest way to think of it is that Google is taking the options you have on your smartphone and splitting them amongst various screens. Let’s say you get a Hangouts notification on your smartphone. In Hangouts, you’ll see the option to reply, archive, or other actions. With Android Wear, you’d have to swipe to a different screen to select your intent.