What is this class/component?

It’s an automatic component of any UI button which is created.

I would like to know what class it is, so i can get references to it, read and set its properties, and maybe even add more copies of it.

I’ve tried using the little gears to select Copy Component, and then Paste Component as New. but for some reason i can’t seem to have more than one of it on the button.

http://docs.unity3d.com/ScriptReference/UI.Image.html ?

As LeftyRighty said, it’s a UI.Image

To hold a reference and modify it’s properties in code, you must have “using namespace UnityEngine.UI;” at the top, or refer to it as UnityEngine.UI.Image.

Hooray, that’s something.
So now that i know what it is, i found it in the add component menu and tried to add another one. Can someone explain this?

I need to have two images on one button (a background/border, and an icon/picture infront of it). Is there any way to do it aside from having the second image on a child object?

Can only have one Image component per GameObject.

If you need 2, make them child gameobjects, and attach an image to each individually.

Adding to what @lordofduct said above, you should make a blank game object and put the two children images below it as peers (same level in the hierarchy). That way you can control their draw order, and any transforms applied to their parents apply to both equally, and you can confidently adjust their relative position and sizes.