Abstract: Disclosed is a method and apparatus for inputting characters as many as possible with a limited number of keys.

Abstract: Disclosed is a method and apparatus for conveniently inputting characters with both hands and inputting characters as many as possible with a limited number of keys.

Abstract: Disclosed herein is a device for rotating or translating a three-dimensional object using a 3×3 button array, in which an application program runs to rotate and to translate a predetermined three-dimensional object on a display screen. The device comprises a button-part including 9 buttons of a 3×3 array and having combinations of buttons on horizontal, vertical, and diagonal lines, corresponding to the direction of rotation or translation of a three-dimensional object on the three-dimensional axis of rotation or along the axis of translation; and a microcomputer for recognizing the depression combination of buttons, the order of the button depressed, and the key-depressing time and outputting a control signal so as to rotate or to translate a portion of or whole configuration of the three-dimensional object on the display screen.