The first 'computer bug' was a literal bug — a moth found inside Harvard's Mark II computer in 1947
Some trivia is so bizarre it forces you to rethink your entire understanding of the world. Check out the fact below, see how others reacted, and scroll down to dive into the verified science and history behind it.
On September 9, 1947, operators of the Harvard Mark II computer found a moth trapped in Relay #70 of Panel F, causing a malfunction. It was taped into the operators' logbook with the note 'First actual case of bug being found.' The term 'bug' for a technical fault predates this — engineers had used it since at least the 19th century — but this incident cemented its use in computing. Grace Hopper, who later invented the first compiler, was the team leader; she didn't find the moth herself but popularised the story.
Software 'bugs' are so abstract and metaphorical that their origin as a literal insect feels too convenient to be true. That it really happened — preserved in a logbook with the actual moth taped in — makes the origin of ubiquitous tech vocabulary delightfully concrete.
The Science Behind It
On September 9, 1947, operators of the Harvard Mark II computer found a moth trapped in Relay #70 of Panel F, causing a malfunction. It was taped into the operators' logbook with the note 'First actual case of bug being found.' The term 'bug' for a technical fault predates this — engineers had used it since at least the 19th century — but this incident cemented its use in computing. Grace Hopper, who later invented the first compiler, was the team leader; she didn't find the moth herself but popularised the story.
Why Your Brain Finds This Hard to Believe
OddlyHuman Editorial
VerifiedWritten and fact-checked by the OddlyHuman Behavioral Science Team. We verify all psychological, sociological, and historical claims against peer-reviewed journals, primary sources, and established encyclopedias to bring you accurate insights.
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