A control device to control a system having an image forming apparatus configured to form an image on a sheet based on an image forming job, and a sheet discharge apparatus having stacking trays on which the sheet having the image formed on the sheet is to be stacked, the control device comprising: storing means configured to store stacking state information indicating a stacking status of sheets for each stacking tray; generating means configured to generate a system configuration image representing a configuration of the system, and to generate sheet bundle images representing sheet bundles stacked on the stacking trays based on the stacking state information stored in the storing means; display control means configured to display, on a display, a screen in which the sheet bundle images are mapped at positions of the stacking trays in the system configuration image; and selecting means configured to select an image forming job corresponding to sheets to be taken out, characterized in that: the sheet bundle images displayed in the display include: a first sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a first stacking tray among the stacking trays; a second sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a second stacking tray among the stacking trays; and a third sheet bundle image representing a sheet bundle of an image forming job which is not designated by the selecting means; wherein the display control means is configured to display, on the display, the first sheet bundle image and the second sheet bundle image in a display color different from that of the third sheet bundle image; and wherein the display control means is configured to display, on the display, an order of the first sheet bundle image and the second sheet bundle image, wherein the order represents a sequence of taking out the first sheet bundle and the second sheet bundle. storing means configured to store stacking state information indicating a stacking status of sheets for each stacking tray; generating means configured to generate a system configuration image representing a configuration of the system, and to generate sheet bundle images representing sheet bundles stacked on the stacking trays based on the stacking state information stored in the storing means; display control means configured to display, on a display, a screen in which the sheet bundle images are mapped at positions of the stacking trays in the system configuration image; and selecting means configured to select an image forming job corresponding to sheets to be taken out, characterized in that: the sheet bundle images displayed in the display include: a first sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a first stacking tray among the stacking trays; a second sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a second stacking tray among the stacking trays; and a third sheet bundle image representing a sheet bundle of an image forming job which is not designated by the selecting means; wherein the display control means is configured to display, on the display, the first sheet bundle image and the second sheet bundle image in a display color different from that of the third sheet bundle image; and wherein the display control means is configured to display, on the display, an order of the first sheet bundle image and the second sheet bundle image, wherein the order represents a sequence of taking out the first sheet bundle and the second sheet bundle. the sheet bundle images displayed in the display include: a first sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a first stacking tray among the stacking trays; a second sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a second stacking tray among the stacking trays; and a third sheet bundle image representing a sheet bundle of an image forming job which is not designated by the selecting means; a first sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a first stacking tray among the stacking trays; a second sheet bundle image representing a sheet bundle of the image forming job which is designated by the selecting means and stacked on a second stacking tray among the stacking trays; and a third sheet bundle image representing a sheet bundle of an image forming job which is not designated by the selecting means; wherein the display control means is configured to display, on the display, the first sheet bundle image and the second sheet bundle image in a display color different from that of the third sheet bundle image; and wherein the display control means is configured to display, on the display, an order of the first sheet bundle image and the second sheet bundle image, wherein the order represents a sequence of taking out the first sheet bundle and the second sheet bundle.