SMD tact switches are tiny tactile switches designed for surface-mount technology (SMD), meaning they can be directly soldered onto the surface of a printed circuit board (PCB) without using wires or through-holes.

These switches are widely used in compact electronic devices, such as smartphones, remote controls, and wearable gadgets, where space is limited. They provide momentary contact and tactile feedback, allowing the user to feel when the button is pressed.

In simple terms, an SMD tact switch is a small, surface-mounted button that temporarily completes a circuit when pressed.