An image forming device includes; a control unit acting as a display control section, an operation receiving section and a controller; and a display section having a touch panel function of sensing proximity and contact of an object to and with a display screen. The display control section displays an operation image in which icons are arranged on the display screen. When the operation receiving section receives a user operation of instructing execution of a function of one of the icons, the controller executes the function. After the operation receiving section receives a user operation of putting an object close to one of the icons, when the state where the object is close to the icon continues for a predetermined time, the display control section displays an explanatory image including the icon and an explanatory note describing the function of the icon in the whole area of the display screen.