Membrane Switch keypad is an interface between man & machine, also called as User Interface or Human Machine Interface. A membrane switch is a simple electro mechanical device used to direct the flow of low voltage, low current electricity through an electrical circuit for turning a circuit on and off. It contains a circuit, printed on special coated polyester films or used glass epoxy printed circuit board [PCB]. Membrane switches are user-equipment interface utilities that allow for the communication of commands from users to electronic devices. It can be thought of as one category of interface utilities alongside touch screens, plastic keyboards, toggle switches and many other kinds of control systems.