Execution commands corresponding to the type of gesture are stored and by acquiring coordinate values of accepted handwriting input including gesture on a display screen, handwriting is displayed. When handwriting input is accepted, display data of handwriting is updated. When handwriting input is not completed, it is decided whether or not handwriting input is gesture input. When it is decided that the handwriting input is gesture input, the type of gesture is decided on the basis of the coordinate values of gesture on the display screen, an execution command corresponding to the type of gesture is read and the fact that the handwriting input is gesture input is displayed. When gesture input is completed, the execution command corresponding to gesture input is executed. Therefore, the user can make handwriting input according to the user's intent without performing mode switching.