The Hollerith card (or "punch" card) is a recording medium for holding information for use by automated data processing machines. Made of thin cardboard, the punch card represents information by the presence or absence of holes in predefined positions on the card. In the first generation of computing, from the 1920s into the 1950s, punch cards were the primary medium for data entry, storage and processing.
Today, punch cards are long obsolete outside of a few legacy systems and specialized applications, having been replaced by magnetic and optical storage media.
History of Computers
History of Programming Languages