First Computer Bug Found: A Moth in the Machine
Grace Hopper's team at Harvard found a moth trapped in Relay #70, Panel F, of the Mark II computer on September 9, 1947, and taped it into the logbook with the annotation "First actual case of bug being found." The term "bug" for a technical malfunction predated the incident by decades: Thomas Edison used it in 1878. But the Harvard moth became the most famous literal bug in computing history, and the logbook page is preserved at the Smithsonian National Museum of American History. Hopper herself became one of the most influential figures in computer science, developing the first compiler and laying the groundwork for COBOL, a programming language still used in banking and government systems today.
September 9, 1947
79 years ago
Key Figures & Places
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