An analog sensor provides a continuous output signal that represents the measured quantity with a range of possible values. It directly measures a physical parameter, such as temperature, pressure, light intensity, or voltage, and converts it into a proportional analog voltage or current signal.

A digital sensor provides discrete or digital output signals that represent specific states or levels of the measured paramter. Instead of providing continuous range of values, it produces binary signals that are either on or off, high or low, or in the form of digital codes.