punched card
Quick Summary
A punch card is a piece of stiff paper in which holes are punched in designated positions to represent data. These cards were an early method of data processing and machine programming.1
The Jacquard loom, invented in the early 19th century, used punched cards to automatically control weaving patterns. This demonstrated that machines could be programmed to perform different tasks by feeding them instructions via punched cards.2
Later, Herman Hollerith adapted punch cards for data tabulation, notably for the U.S. census. IBM developed the Port-A-Punch, which featured pre-scored holes to improve accuracy. Punch cards were adapted for voting machines in the 1960s, but issues with "chads" (partially detached punched paper) led to their eventual ban in U.S. elections by the Help America Vote Act of 2002. While largely supplanted by modern technologies, punched cards were a foundational element in the history of computing and data processing.34
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Analytical Engine…were to be entered on punched cards, using the card-reading technology of the Jacquard loom. Instructions were also to be entered on cards, another idea taken directly from Joseph-Marie Jacquard. The use of instruction cards would make it a programmable device and far more flexible than any machine then in…
Read More…were to be entered on punched cards, using the card-reading technology of the Jacquard loom. Instructions were also to be entered on cards, another idea taken directly from Joseph-Marie Jacquard. The use of instruction cards would make it a programmable device and far more flexible than any machine then in…
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computerThe Analytical Engine…were to be entered on punched cards, using the card-reading technology of the Jacquard loom. Instructions were also to be entered on cards, another idea taken directly from Jacquard. The use of instruction cards would make it a programmable device and far more flexible than any machine then in existence.…
Read More…were to be entered on punched cards, using the card-reading technology of the Jacquard loom. Instructions were also to be entered on cards, another idea taken directly from Jacquard. The use of instruction cards would make it a programmable device and far more flexible than any machine then in existence.…
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Jacquard loomJacquard’s loom used interchangeable punched cards that controlled the weaving of the cloth so that any desired pattern could be obtained automatically. These punched cards were adopted by the English inventor Charles Babbage as an input-output medium for his proposed Analytical Engine (which would have been the first digital…
Read MoreJacquard’s loom used interchangeable punched cards that controlled the weaving of the cloth so that any desired pattern could be obtained automatically. These punched cards were adopted by the English inventor Charles Babbage as an input-output medium for his proposed Analytical Engine (which would have been the first digital…
Read More- computerThe Jacquard loom
By inserting a card punched with holes, an operator could control the motion of the rods and thereby alter the pattern of the weave. Moreover, the loom was equipped with a card-reading device that slipped a new card from a pre-punched deck into place every time the shuttle…
Read MoreBy inserting a card punched with holes, an operator could control the motion of the rods and thereby alter the pattern of the weave. Moreover, the loom was equipped with a card-reading device that slipped a new card from a pre-punched deck into place every time the shuttle…
Read More