(plural punch cards)
- A card that can have holes or notches cut in it, especially one for storing data, that can be sorted according to combinations of holes present or absent.
- (computing) Such a card, the size of a US dollar bill, having 80 columns of 12 rows used in early mainframe computers.
- A card given to a customer and punched with a hole at each purchase, allowing a reward to be claimed when fully punched.
punch card - Computer Definition
(1) See loyalty punch card.
(2) An early storage medium made of thin cardboard stock that held data as patterns of punched holes. Also called "punched" cards, each of the 80 or 96 columns held one character. The holes were punched by a keypunch machine or card punch peripheral and were fed into the computer by a card reader. From 1890 until the 1970s, punch cards were synonymous with data processing. The concepts were simple: the database was the file cabinet; a record was a card. Processing was performed on separate machines called "sorters," "collators," "reproducers," "calculators" and "accounting machines." Today, the punch card is all but obsolete except for voting systems in some states. The presidential election of 2000 brought punch cards into infamy and made the U.S. the brunt of jokes worldwide for using such antiquated and error-prone systems. The solution in many states was to migrate to electronic voting machines, which happened to be developed without audit trails so that ballots could never be recounted in close elections (see e-voting). So much for progress! See sorter, tabulator and Hollerith machine.