PURPOSE: To master the operating function of a keyboard in a short time by applying a prescribed contrivance to the array of keys or the form of a keyboard.

CONSTITUTION: The keys 2 are arrayed so that each finger can operate two keys 2 respectively when a hand H is put over an operating board 1. That is, 20 keys 2 can be operated in all by both hands. The projection and recess parts of the board 1 are fitted to the recess and projection parts of a palm respectively when the hand H is put over the board 1. These projection and recess parts support the empty weight of the hand and the arm and function to guide each finger to keys 2 and to give the supporting power when keys 2 are operated. In addition, the board 1 is supported approximately horizontal and rotatably by a support board 3 when the hand H is put on the board 1. A shift switch 4 is actuated by the rotation of the board 1. Therefore, the switch 4 can be operated just with the palm force without using fingers. In such a way, the operating function of a keyboard can be mastered in a short time.