Why Does't This Work!?!?

Ok this makes no sense I just want to make a simple GUI label, but I get a error and have no idea why! Here is the script:

function OnGUI(){
    GUI.Label(Rect(10, 10, 20, 10), "this is a GUI");
}

What error do you get?

Have you attached this script to an object within the scene that is active?

From what I see, your code should be 100% working.

You might want to consider making your label bigger width wise, or else it will 'hide' the label. Try this:

function OnGUI(){
    GUI.Label(Rect(10, 10, 200, 20), "this is a GUI");
}