A user input apparatus according to the present invention is configured like a
wrist watch and a system can recognize the gesture such as "grip" and "release"
or the like and can input the gesture as a command merely by attaching the user
input apparatus to user's wrist. Further, by adding an acceleration sensor or the
like for measuring the movement of an arm itself to a bracelet, the user input
apparatus can be configured so as to input more complicated instruction and command.
The user input apparatus can be used as an input apparatus for a wearable computer
(or wearable computer), or a controller to input a command for a game machine or