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keypunch machine

A punch-card data entry machine. A deck of blank cards was placed into a hopper, and, upon operator command, the machine fed one card to a punch station. As characters were typed, a series of dies at the punch station punched the appropriate holes in the selected card column.

IBM Keypunch
This is the type of IBM keypunch machine used in the 1960s and 1970s. Operators by the tens of thousands would spend a full shift keypunching orders, time cards and a host of other transactions. (Image courtesy of IBM.)

The First One
Throughout the 1890s, data for 60 million Americans was punched into Hollerith cards from information recorded by census takers. The cards were then "automatically" counted. See Hollerith machine for more details. (Image courtesy of IBM.)

Hollerith machine

The first automatic data processing system. Developed by Herman Hollerith, a Census Bureau statistician, the machine was first used to count the U.S. census of 1890. It was so successful that Hollerith later formed the Tabulating Machine Company and sold his machines throughout the world for a variety of accounting functions. In 1911, his company merged with another company that was later renamed IBM. Following is the sequence of steps used to count the 1890 census. See punch card.

What a Concept!
This form (top) was filled out by census takers for 62 million Americans, and Electrical Engineer featured the process.

Hollerith's Card Punch
The operator read the census forms and punched holes into dollar-bill-sized cards to represent the data. (Image courtesy of IBM.)

The Punch Card Reader
Each card was placed in the reader, and the handle was pulled down. Spring-loaded pins passed through the holes and closed electrical circuits that incremented the counters. (Image courtesy of The Computer History Museum,

The Hollerith System
After pulling the handle, one of the lids on the sorting box (right) opened, and the operator dropped in the card. Saving the government $5 million, it took three years to count the census instead of a decade. (Image courtesy of The Computer History Museum,

High Tech in 1890
The text at the bottom of this August 1890 issue reads "THE NEW CENSUS OF THE UNITED STATES - THE ELECTRICAL ENUMERATING MECHANISM." (Image courtesy of Scientific American Magazine.)

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