The DICT Development Group

  punched card
  
  
      [techspeak] (alt.: punch card) The signature medium of computing's Stone
      Age, now obsolescent. The punched card actually predated computers
      considerably, originating in 1801 as a control device for mechanical looms.
      The version patented by Hollerith and used with mechanical tabulating
      machines in the 1890 U.S. Census was a piece of cardboard about 90 mm by
      215 mm. There is a widespread myth that it was designed to fit in the
      currency trays used for that era's larger dollar bills, but recent
      investigations have falsified this.
  
      IBM (which originated as a tabulating-machine manufacturer) married the
      punched card to computers, encoding binary information as patterns of small
      rectangular holes; one character per column, 80 columns per card. Other
      coding schemes, sizes of card, and hole shapes were tried at various times.
  
      The 80-column width of most character terminals is a legacy of the IBM
      punched card; so is the size of the quick-reference cards distributed with
      many varieties of computers even today. See chad, chad box, {
      eighty-column mind, green card, dusty deck, code grinder.