The Development of Telephone

The development of wired telephones, from the generation of signals by the handle of hand cranked telephones, to the rotary dialing of dial phones, and then to the digital input of button phones, each step marks technological progress and improvement in user convenience.

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

On June 2, 1875, Bell and his assistant Watson finally succeeded in the test after going through hardships. For over a hundred years, although the basic functions of telephones have not undergone fundamental changes, they have long been "unrecognizable". From the magnetic telephone with a handle, to the dial type automatic telephone, to the keypad telephone and the audible and visible video telephone, it records the footsteps of the telephone for a hundred years.