Telephone history starts at the beginning of human history. As at that time also human tried to communicate with each other by smoke signals, mirror signals, carrier pigeons etc.
Telephone comes from the Greek word “Tele” means afar and “phone” which means voice or voiced sound. Generally, telephone is a device which transfers sound mainly the human voice over a distance.
Probably nothing except telephone has revolutionized the ordinary human communication from one place to another considered the distance is long.
Telephone is a device which converts the sound specially the human voice into electronic impulses and transfer’s the impulses back to a tone which is just like human voice.