A transducer is a device that converts the change in a physical quantity such as pressure, temperature, sound to an electrical signal or vice versa.
The transducer converts the information which is in the form of sound, music, pictures or computer data to electrical signals.
The microphone is an example of a transducer that converts sound energy into electrical energy.
Transducer in communication system
The transducer is simply a device that converts energy from one form to another. It is used in automation, control systems, measurements, etc.
The process of converting the energy of one form to another form is called transduction.
It converts propagating electromagnetic waves to and from conducted electrical signals.
Tape Head, disk read and Write Heads
It covers the magnetic field on tape or cd/DVD to and from electrical signals.
It converts sound into an electrical signal.
It converts the electrical signal into sound.