A push-button is a human-operated switch that changes the state of an electrical connection when pressed. Typical push-buttons are small, circular, or rectangular actuators that, by mechanical or electronic means, either close or open an electrical circuit to send a control signal or operate a device.
How they work
Push-buttons can be constructed to behave in two basic ways:
- Momentary — the circuit is completed only while the button is held down; releasing it returns the contact to its previous state.
- Maintained (latching) — pressing the button changes its state until it is pressed again to switch back.
Internally, actuation may rely on metal contacts, dome switches, rubber membranes, or electronic sensors. Some designs include tactile feedback (a click) or illumination so the user can see the button's status.
Common applications
- Domestic and commercial signaling, for example a doorbell.
- Input devices on small electronics such as a calculator, remote controls, and hand-held instruments.
- Controls on arcade machines, elevators, industrial panels, appliances, and many other human–machine interfaces.
Design considerations
- Ergonomics and size — buttons must be large enough to press reliably and placed where users expect them.
- Durability — rated for a certain number of operations and, where needed, for resistance to dust and moisture.
- Electrical ratings — chosen to match the voltage and current of the circuit they control.
- Safety and standards — in many settings button designs follow regulations appropriate to the application, such as emergency stop controls in industrial environments.
Because push-buttons provide an intuitive way to command electronic and electromechanical systems, they remain a widespread interface element across consumer products and industrial equipment.