Abstract: A data processor such as a household information system which is realized by an image display with which the initial image of the system changes every time the system is started, and the displayed object moves interactively, employing a small memory. When the power source of the processor is turned on, the initial image display processing unit is started. In the initial image display processing unit, the screen display update processing unit changes the image on the display unit every after a predetermined period of time based upon the state of the images that have been stored in advance in the state storage unit. Moreover, any input from the input unit is detected by the input detect unit. Then, the image state select processing unit selects the state of a new image that corresponds to the input and stores it in the state storage unit.