facebook ads: what are "actions"

I decided to try facebook ads for kicks and giggles.

So I'm reading the stats, and have no idea what "Actions" column means. Does that mean that the visitor decided to "like" your page or what? I looked in the Ad Glossary and they don't even define it.

it generally means what they've looked at - if it says "16" in the actions column (or whatever) it means they've been to "16" items - maybe albums or photos.

I think its the sum of comments, likes and all the other stuff that someone has made on your photos/posts/videos

Ok, that's cool. So it'll only record an action if that person clicks the ad, which redirects to my facebook page, and then if they "like" something or make a comment on something, that is an action? So if they just come to my page, read, don't comment or like anything, and then leave, that is 0 actions. How about if they come to the page, don't like or comment an item on the page, but then adds the page itself to it's list of "likes", does that qualify as an action? I'm just trying to find out if the number of "likes" I'm getting is from the ads or not.