Log Book With Computer Bug

Log Book With Computer Bug

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American engineers have been calling small flaws in machines "bugs" for over a century. Thomas Edison talked about bugs in electrical circuits in the 1870s. When the first computers were built during the early 1940s, people working on them found bugs in both the hardware of the machines and in the programs that ran them. 
In 1947, engineers working on the Mark II computer at Harvard University found a moth stuck in one of the components. They taped the insect in their logbook and labeled it "first actual case of bug being found." The words "bug" and "debug" soon became a standard part of the language of computer programmers.
Among those working on the Mark II in 1947 was mathematician and computer programmer Grace Hopper, who later became a Navy rear admiral. This log book was probably not Hopper's, but she and the rest of the Mark II team helped popularize the use of the term computer bug and the related phrase "debug."
Grace Murray Hopper,"The First Bug," Annals of the History of Computing,vol. 3 #3, 1981, pp. 285-286.
P. A. Kidwell, "Stalking the ElusiveComputer Bug," IEEE Annals of the History of Computing, vo.20, #4, 1998, pp.5-9.
Currently not on view
Object Name
log book
Date made
Aiken, Howard Hathaway
Harvard University
Harvard University
Aiken, Howard
Place Made
United States: Massachusetts, Cambridge
Physical Description
tape (overall material)
paper (overall material)
cloth (overall material)
ink (overall material)
biologicals (overall material)
overall: 1.5 cm x 48.4 cm x 29.5 cm; 9/16 in x 19 1/16 in x 11 5/8 in
ID Number
catalog number
accession number
Credit Line
Transfer from United States Department of Defense, Naval Surface Warfare Center
Computer Bug
See more items in
Medicine and Science: Computers
Computers & Business Machines
Data Source
National Museum of American History
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As a computer science student, I hear this story all the time, but it never gets old!
As a former sailor and Plankowner of her Namesake... the term Bug and debugging were both coined by none other that former "Amazing" Grace Hopper who would go on to become a Navy Admiral and serve nearly 4 decades in the U.S. Navy. She has a US warship named after her the USS HOPPER DDG-70. She was one of only 3 Female Admirals and would become a legend in the US Navy. She was retired and asked to come out of retirement on 3 separate occasions.
I agree that she played a hand in it, but we can't say that Edison coined it first in the 1800's and have it again coined first in the late 1940's. We can declare that the group she was a part of defined the "software" versions. Shout out to all the early programmers who brought forth our computing prowess!
Has anyone identified the moth in question?
Although I am not an entomologist, it appears to be Biston betularia (peppered moth). Source: Schuppli, S. (2008). Of Mice Moths and Men Machines. Cosmos and History: The Journal of Natural and Social Philosophy, 4(1-2), 286–306. Retrieved from https://mail.cosmosandhistory.org/index.php/journal/article/view/103
I'm sure it was documented somewhere before. A quick Internet search will yield results, I wager.

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