To provide a method and device for inputting data with which informa tion can be inputted to a computer system while using natural human actions.

The motion of the head of device user is detected by a head motion detection part(HMD) 7 built in spectacles. When the device user performs the action of nodding corresponding to a message calling the answer of 'yes' or 'no' displayed on an information processor (device), for example, the device catches this action as the rotation around a row axis and regards it as the answer, 'yes.' On the contrary, when the user of the device performs the action of 'shaking the head,' the device catches this action as the rotation around a pitch axis and regards it as the answer, 'no'.