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Article: Tabulating Machines
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- Computer Sciences
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CopyrightCOPYRIGHT 2002 The Gale Group Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Tabulating Machines
Tabulating machines, or
punched card
machines, were the earliest automated data processing devices. They include keypunch machines, collators, sorters, reproducers, and tabulators. By the late 1980s, virtually all tabulating machines had been replaced by digital computer systems.
A keypunch machine was a data entry device that punched holes in a lightweight piece of cardboard. A deck of blank cards was placed in a hopper. A keypunch operator signaled a punched card to be loaded into the punching station of the machine. As the operator typed on a keyboard, a series of dies punched predefined holes in the selected card column. One or more holes in a vertical column ...