Grace Murray Hopper

Captain Grace Murray Hopper (1976)

Admiral Grace Hopper, who invented COBOL, liked to tell a story in which a technician solved a glitch in the Harvard University Mark II Aiken Relay Calculator by pulling a moth from between the contacts of one of its relays.

First Computer Bug

Moth found trapped between points at Relay # 70, Panel F, of the Mark II Aiken Relay Calculator while it was being tested at Harvard University, 9 September 1945. The operators affixed the moth to the computer log, with the entry: "First actual case of bug being found". They put out the word that they had "debugged" the machine, thus introducing the term "debugging a computer program".