A printing system is provided having interactive sample page preview and selection capabilities. The cooling device comprises a self-contained unit. The form of the projection part is made highest in a vicinity of a central part of the clip and lowest at both end parts of the plate-like member. Information may also be encoded by the shape of the colored image pattern. The electronic storage unit can be readily removed from the console. Further, various subsystems are considered, such as fuel vapor purging, air-fuel ratio control, engine torque control, catalyst design, and exhaust system design.