punched card

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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 ?
Also, because the candidates' names and ballot-measure identifiers do not appear on booklet-type punch-card ballots, voters may not be able to tell from a visual inspection if they cast their votes as they intended.
At her first news conference as chair of the Congressional Black Caucus, Texas Representative Eddie Bernice Johnson called on Congress to replace the punch-card machines.
The first proposal on the table is the immediate removal of all the Sunshine State's punch-card ballot machines in favor of optical scanners.
That is, a disproportionate number of voters done in by the error-prone punch-card machines were low-income and black Floridians, who generally favored Al Gore over George W.
Assuming that its attached punch-card reader sensed the voters' choices correctly, a central computer would then count the votes.
After relying on punch-card ballots for more than 30 years, officials agreed in 2004 to replace them under a federal consent decree.
Given these high stakes, Gumbel might have been expected to explore every possible alternative to the DREs and punch-card machines that dominate current elections.
Elections manager Annette Newingham said that not only will the scanning equipment take up much more room than the old punch-card readers, but the county will need a lot more storage room to store the much-larger paper ballots for the time period required by law.
His office, adorned with butterfly ballots, a punch-card machine, and photos of judges examining chads, is a monument to what can go wrong without an effective election plan.
The punch-card system came in for a lot of well-founded criticism, and the new system will be more reliable in case of disputes.
Some of the areas that must be addressed immediately under federal law include the statewide replacing of punch-card voting systems, the requirement of a paper record of every election ballot cast and the establishment of a federally mandated database throughout the state that will ensure that only eligible voters are able to cast ballots.
The days of punch-card ballots are numbered in Lane County.