Included with many older console games, overlays are a thin piece of plastic that slides over the buttons on a keypad, labeling the keys for the functions that pertain to that game.
Typically a printed decal or engraved product designed to be applied on top of or around (or overlay) fasteners, spaces, lights, etc. and provide a unified, finished appearance for specific areas of a product. Overlays are used to provide a one-piece installation to label multiple devices such as buttons, switches & displays. Overlays also typically utilize dead space between devices or added margins to display graphics, logos, and/or additional information such as safety messages, instructions, function labels, etc. See Bezel and Membrane Switch. VIEW SAMPLE OVERLAYS.