An apparatus and method is disclosed wherein motion data which define motions of an end effecter of a robot such as a hand tip can be produced simply and conveniently. The apparatus and method provide a motion editing environment in which motion data for allowing a robot to plot a picture or a character can be edited simply and conveniently based on interactions such as hand-written inputting of a user through a mouse, a tablet or the like. By reproducing the produced motion data on a robot, a motion of plotting an arbitrary character or picture by the robot can be implemented simply.