An incremental encoder is an electromechanical device that converts the angular position or motion of a shaft into a series of electrical signals (pulses). Unlike an absolute encoder, which knows its exact position at all times, an incremental encoder tracks changes in position relative to a starting point.

Think of it like a trip odometer in your car: it doesn't tell you where you are on a global map, but it tells you exactly how far you have traveled since you hit reset.