Telephone [English: telephone, from Greek τ? λε(tēle, meaning "far") and φ ω ν? (ph n ē, meaning "sound"), the old translation is a long-distance communication device, which can transmit and receive sound. As early as the18th century, there was a word "telephone" in Europe, which was used to refer to microphones strung together with wires (cups strung together with wires).
The telephone was attributed to Alexander Graham Bell. The principle of early telephone is that sound is a compound vibration in the air, which can be transmitted to solids and to conductive metals through electric pulses. Bell applied for the telephone patent in March 1876.
On June 5th, 2002, the United States Congress confirmed Antonio Muzzi as the inventor of the telephone. Zi Mu first showed his invention to the public on 1860, and published an introduction in an Italian newspaper in new york.
The improvements and inventions of telephone in history include: toner microphone, manual switchboard, dial, automatic telephone exchange, program-controlled telephone exchange, dual-tone multi-frequency dialing, voice digital sampling and so on. New technologies in recent years include ISDN, DSL, VoIP, analog mobile phone and digital mobile phone.