Punched card

A punched card (also punch card^[1] or punched-card^[2]) is a piece of card stock that stores digital data using punched holes. Punched cards were once common in data processing and the control of automated machines.

"Overpunch" redirects here. For the COBOL code, see Signed overpunch.

Punched cards were widely used in the 20th century, where unit record machines, organized into data processing systems, used punched cards for data input, output, and storage.^[3]^[4] The IBM 12-row/80-column punched card format came to dominate the industry. Many early digital computers used punched cards as the primary medium for input of both computer programs and data.

Data can be entered onto a punched card using a keypunch.

While punched cards are now obsolete as a storage medium, as of 2012, some voting machines still used punched cards to record votes.^[5] Punched cards also had a significant cultural impact in the 20th century.

IBM Port-A-Punch

FORTRAN Port-A-Punch card. Compiler directive "SQUEEZE" removed the alternating blank columns from the input.

Port-a-punch

Accommodation of people's names: The Man Whose Name Wouldn't Fit^[78]

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Artist and architect in 2004 designed a public art installation at Ohio University, titled "Input", that looks like a punched card from the air.^[79]

Maya Lin

Tucker Hall at the University of Missouri – Columbia features architecture that is rumored to be influenced by punched cards. Although there are only two rows of windows on the building, a rumor holds that their spacing and pattern will spell out "M-I-Z beat k-U!" on a punched card, making reference to the university and state's rivalry with neighboring state Kansas.

[80]

At the University of Wisconsin – Madison, the exterior windows of the Engineering Research Building were modeled after a punched card layout, during its construction in 1966.

[81]

At the University of North Dakota in Grand Forks, a portion of the exterior of Gamble Hall (College of Business and Public Administration), has a series of light-colored bricks that resembles a punched card spelling out "University of North Dakota."

[82]

In the 1964–1965 , punched cards became a

Free Speech Movement

ANSI INCITS 21-1967 (R2002), Rectangular Holes in Twelve-Row Punched Cards (formerly ANSI X3.21-1967 (R1997)) Specifies the size and location of rectangular holes in twelve-row 3+1⁄4-inch-wide (83 mm) punched cards.

ANSI X3.11-1990 American National Standard Specifications for General Purpose Paper Cards for Information Processing

ANSI X3.26-1980 (R1991) Hollerith Punched Card Code

ISO 1681:1973 Information processing – Unpunched paper cards – Specification

ISO 6586:1980 Data processing – Implementation of the ISO 7- bit and 8- bit coded character sets on punched cards. Defines ISO 7-bit and 8-bit character sets on punched cards as well as the representation of 7-bit and 8-bit combinations on 12-row punched cards. Derived from, and compatible with, the Hollerith Code, ensuring compatibility with existing punched card files.

—machines with a keyboard that punched cards from operator entered data.

Keypunches

—machines that process data on punched cards. Employed prior to the widespread use of digital computers. Includes card sorters, tabulating machines and a variety of other machines

Unit record equipment

—a computer input device used to read executable computer programs and data from punched cards under computer control. Card readers, found in early computers, could read up to 100 cards per minute, while traditional "high-speed" card readers could read about 1,000 cards per minute.^[90]

Computer punched card reader

—a computer output device that punches holes in cards under computer control.

Computer card punch

—used into the 21st century

Voting machines

Processing of punched cards was handled by a variety of machines, including:

Aperture card

Book music

Card image

Computer programming in the punched card era

Edge-notched card

History of computing hardware

—punched card price tags

Kimball tag

Paper data storage

Punched card input/output

Punched tape

Lace card

Fierheller, George A. (2014-02-07). (PDF). Markham, Ontario, Canada: Stewart Publishing & Printing. ISBN 978-1-894183-86-4. Archived (PDF) from the original on 2022-07-09. Retrieved 2018-04-03. (NB. An accessible book of recollections (sometimes with errors), with photographs and descriptions of many unit record machines.)

Do not Fold, Spindle or Mutilate: The "hole" story of punched cards

How to Succeed At Cards (Film). . 1963. (NB. An account of how IBM Cards are manufactured, with special emphasis on quality control.)

IBM

(1961). "Chapter 6 Punched Cards". Mathematical Machines: Digital Computers. Vol. 1. Columbia University Press. (NB. Includes a description of Samas punched cards and illustration of an Underwood Samas punched card.)

Murray, Francis Joseph

Solomon, Jr., Martin B.; Lovan, Nora Geraldine (1967). Annotated Bibliography of Films in Automation, Data Processing, and Computer Science. .

University of Kentucky

Dyson, George (1999-03-01). . Wired. Vol. 7, no. 3. Archived from the original on 2022-07-09. Retrieved 2017-07-04. (NB. Article about use of punched cards in the 1990s (Cardamation).)

"The Undead"

Williams, Robert V. (2002). . IEEE Annals of the History of Computing: Web Extra. 24 (2). IEEE. Archived from the original on 2018-06-13. Retrieved 2015-03-26.

"Punched Cards: A Brief Tutorial"

An Emulator for Punched cards

at the Wayback Machine (archived 2011-10-17) – a U.S. company that supplied punched card equipment and supplies until 2011.

Cardamation

Atlas Computer Laboratory, 1960

Collected Information on Punched Card Codes

(Director) (1961). 660124: The Story of an IBM Card (Film).

Brian De Palma

Jones, Douglas W. . Retrieved 2006-10-20. (Collection shows examples of left, right, and no corner cuts.)

"Punched Cards"

– a collection at Gesellschaft für Software mbH

Punched Cards

(Shows examples of both left and right corner cuts.)

UNIVAC Punch Card Gallery

– a U.S. company that converts punched cards to conventional media