Hollerith Card Puncher, an integral part of the tabulation system used by the United States Census Bureau to compile the thousands of facts gathered by the Bureau. Holes are punched in the card according to a prearranged code transferring the facts from the Census questionnaire into statistics. A punched card reader or just card reader is a computer input device used to read data from punched cards. A card punch is an output device that punches holes in cards under computer control. Sometimes card readers were combined with card punches and, later, other devices to form multifunction machines. Many early computers, such as ENIAC, used punched card input/output. Photograph, circa 1940, appears to be staged as it shows a Hollerith pantograph with a keyboard for the 1920 population card.