Noob - Use the ESC, Shift and Command Key??

Hello,

For a Input.GetButtonDown /or/ Input.GetKeyDown, how would I apply it to the ESC key, shift and command key? I tried using:

Input.GetKeyDown("ESC"); Input.GetButtonDown("ESC");

and nothing, what do I need to do?

Use Input.GetKeyDown("escape") or Input.GetKeyDown(KeyCode.Escape).

Reference for KeyCodes