punched card

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Related to Punch cards: Hollerith card, Charles Babbage

punched card

(esp US), punch card
(formerly) a card on which data can be coded in the form of punched holes. In computing, there were usually 80 columns and 12 rows, each column containing a pattern of holes representing one character

punched card

[′pəncht ‚kärd]
(computer science)

punched card

(storage, history)
(Or "punch card") The signature medium of computing's Stone Age, now long obsolete outside of a few legacy systems. The punched card actually predates computers considerably, originating in 1801 as a control device for Jacquard looms. Charles Babbage used them as a data and program storage medium for his Analytical Engine:

"To those who are acquainted with the principles of the Jacquard loom, and who are also familiar with analytical formul?, a general idea of the means by which the Engine executes its operations may be obtained without much difficulty. In the Exhibition of 1862 there were many splendid examples of such looms. [...] These patterns are then sent to a peculiar artist, who, by means of a certain machine, punches holes in a set of pasteboard cards in such a manner that when those cards are placed in a Jacquard loom, it will then weave upon its produce the exact pattern designed by the artist. [...] The analogy of the Analytical Engine with this well-known process is nearly perfect. There are therefore two sets of cards, the first to direct the nature of the operations to be performed -- these are called operation cards: the other to direct the particular variables on which those cards are required to operate -- these latter are called variable cards. Now the symbol of each variable or constant, is placed at the top of a column capable of containing any required number of digits."

-- from Chapter 8 of Charles Babbage's "Passages from the Life of a Philosopher", 1864.

The version patented by Herman Hollerith and used with mechanical tabulating machines in the 1890 US Census was a piece of cardboard about 90 mm by 215 mm. There is a widespread myth that it was designed to fit in the currency trays used for that era's larger dollar bills, but recent investigations have falsified this.

IBM (which originated as a tabulating-machine manufacturer) married the punched card to computers, encoding binary information as patterns of small rectangular holes; one character per column, 80 columns per card. Other coding schemes, sizes of card, and hole shapes were tried at various times.

The 80-column width of most character terminals is a legacy of the IBM punched card; so is the size of the quick-reference cards distributed with many varieties of computers even today.

See chad, chad box, eighty-column mind, green card, dusty deck, lace card, card walloper.
References in periodicals archive ?
With punch cards you sometimes don't punch hard enough where you're supposed to punch, or punch twice when you meant to punch once.
And while punch cards are still being used in at least parts of 22 states, according to the Election Reform Information Project, a tracking effort sponsored by the Pew Charitable Trusts through the University of Richmond, steps are being taken to upgrade balloting systems throughout the country.
Computer punch cards have, in large part, gone the way of the eight-track tape, but Allan Co.
The state brought in the machines after outlawing their old punch card systems in the wake of the 2000 US presidential election recount debacles.
His holes are 10 nanometers, or billionths of a metre, in size and about three billion of them fit in a punch card hole.
MTS packaging equipment, which ranges from small manual machines to fully automated high-volume systems, allows pharmacies to assemble, fill and seal tablets or capsules into blistered punch cards, enabling them to reduce staffing requirements and make operations more cost-efficient, notes Siegel.
In Chicago punch cards were used and the error rate was 7.
Two-thirds of the state's black voters reside in counties using punch cards, while 56 percent of white voters do.
The central hub of any SOHO is a personal computer, so if you still have a unit that uses punch cards and vacuum tubes -- it's definitely time to upgrade.
He made use of punch cards after the fashion of Jacquard (see 1801) and Babbage (see 1822).