Search results
Results From The WOW.Com Content Network
Punched cards. A punched card is a flexible write-once medium that encodes data, most commonly 80 characters. Groups or "decks" of cards form programs and collections of data. The term is often used interchangeably with punch card, the difference being that an unused card is a "punch card," but once information had been encoded by punching ...
Punched card input/output. A computer punched card reader or just computer card reader is a computer input device used to read computer programs in either source or executable form and data from punched cards. A computer card punch is a computer output device that punches holes in cards. Sometimes computer punch card readers were combined with ...
Punched card. A 12-row/80-column IBM punched card from the mid-twentieth century. A punched card (also punch card[ 1] or punched-card[ 2]) is a piece of card stock that stores digital data using punched holes. Punched cards were once common in data processing and the control of automated machines . Punched cards were widely used in the 20th ...
Signed overpunch. In computing, a signed overpunch is a coding scheme which stores the sign of a number by changing (usually) the last digit. It is used in character data on IBM mainframes by languages such as COBOL, PL/I, and RPG. [1] Its purpose is to save a character that would otherwise be used by the sign digit. [2]
Herman Hollerith (February 29, 1860 – November 17, 1929) was an American statistician, inventor, and businessman who developed an electromechanical tabulating machine for punched cards to assist in summarizing information and, later, in accounting. His invention of the punched card tabulating machine, patented in 1884, marks the beginning of ...
Hollerith punched card. The tabulating machine was an electromechanical machine designed to assist in summarizing information stored on punched cards. Invented by Herman Hollerith, the machine was developed to help process data for the 1890 U.S. Census. Later models were widely used for business applications such as accounting and inventory ...
The IBM 519 Document-Originating Machine, introduced in 1946, was the last in a series of unit record machines designed for automated preparation of punched cards. Others in the series included the IBM 513 & IBM 514 Reproducing Punch. The 519, which was "state of the art for the time", [1] could: The reproducing, gangpunching, summary punching ...
Lace card. A lace card is a punched card with all holes punched (also called a whoopee card, ventilator card, flyswatter card, or IBM doily ). They were mainly used as practical jokes to cause disruption in card readers. Card readers tended to jam when a lace card was inserted, as the resulting card had insufficient structural integrity to ...