Interface - (in terms of Interactive Television) - (Associated with User Interface, Digital TV Interface, Onscreen User Interface.) - (1) The Interface is literally the appearance of the information, data, images etc. that you see on your display. This could be in the form of an Electronic Program Guide (Interactive Program Guide). In interactive TV, typically the interface makes available some form of interactivity.

(2) The elements you use to interact with your TV system. It includes the buttons you push and what's activited on the screen.
See the Interactive Television Institute.