Punched card

A punched card (also punch card[1] or punched-card[2]) is a piece of stiff paper that holds digital data represented by the presence or absence of holes in predefined positions. Punched cards were once common in data processing applications or to directly control automated machinery.

A 12-row/80-column IBM punched card from the mid-twentieth century

Punched cards were widely used through much of the 20th century in the data processing industry, where specialized and increasingly complex unit record machines, organized into semiautomatic 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.

While punched cards are now obsolete as a storage medium, as of 2012, some voting machines still used punched cards to record votes.[5] They also had a significant cultural impact.

Close-up of a Jacquard loom's chain, constructed using 8 × 26 hole punched cards

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