From the early 20th century into the 1970s, Americans used punched cards to enter data onto tabulating equipment and then electronic computers. This early key-operated punch is based on patents of the ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. This machine was used to punch paper ...

Credit: Maria Dryfhout/Shutterstock.com. This month, the U.S. Census Bureau undertakes the 24th national census, beginning with Census Day on April 1. Today's tools for data collection include the ...

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