A type of keyboard design that uses changes in capacitance, or stored static electricity, rather than changes in flows of electricity used by contact keyboards to register when a user has depressed a specific key on the keyboard. Under the keyboard’s keys are capacitors that store electricity as opposite static charges in pairs of conductive plates made from nickel-plated copper that are separated by a non-conductive material (typically some form of plastic). The opposite static charges hold an attractive field between them, but the insulating material prevents the charges from canceling each other out by coming together. When a key is pressed, the pads move closer to each other and change the capacity for storing a charge, which the keyboard detects as a start or stop in the flow of electricity and inputs the correct keystroke.
Capacitive keyboards are more durable than contact keyboards and are resistant to oxidization, which can weaken a keyboard’s mechanics.
