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 ?
Replacement of Punchcard and Lever Machine Systems.
When I graduated from the University of Evansville, Indiana, in 1995, I was the first student to write code in Visual Basic[R], and my class was the first class to graduate never having used punchcards to program a mainframe," Meyers recalls.
Still, the use of punchcards is generally seen as more difficult for voters.
Yakima County previously used a punchcard ballot system.
Respondents reported that the percentage of jurisdictions using lever machines, punchcards, hand-counted paper ballots, and central-count optical scan (CCOS) as their primary voting system decreased substantially, while the percentage using PCOS and DREs increased (see Figure 7).
This suggests that Lane County reduced its error rate by 94 percent by switching to optical scanners from punchcards.
The IT processes used to manage the development and maintenance of business applications have evolved from the days of programming punchcards," said Ian Hayes, principal Clarity Consulting, a Boston-based consulting firm that works with IT organizations to enhance their productivity.
While initial reactions after the election had tended to focus on technological fixes such as eliminating punchcards, some consensus emerged subsequently that the issues, and the solutions needed, are more complex and often involve trade-offs among diverse goals.
Get the ink right, and the new voting system - which replaces the much-maligned punchcards that called the entire 2000 U.
Even worse damage could result if punchcards and other forms of voting are replaced with ATM-style touchscreen machines whose tabulations can't be checked.
The same is true with a computerized counting system when it reads punchcards or optical scan ballots.