What is a transducer?

Basically a transducer is a device that converts energy/signal into another form. For example, force, torque, light, speed, position etc. Conversion of differences in similar physical quantities. And specific applications are in automation, control systems, and measuring to convert physical parameters such as pressure, temperature, level, flow or the like. Brightness etc., in an electrical signal or vice versa. The term transducer is used instead of the term sensor. Transducers are defined as elements that experience relative changes when subjected to some physical change.