A flat, usually programmable, keyboard with numerous pressure sensitive switches located under a soft surface. After areas of the keyboard have been defined, the user activates them by pressing on the surface.
A membrane keyboard is a computer keyboard whose "keys" are not separate, moving parts, as with the majority of other keyboards, but rather have only outlines and symbols printed on a flat, flexible surface. Very little, if any, tactile feedback is felt when using such a keyboard, and error-free blind typing can be difficult.