The first 'computer bug' was a literal bug — a moth found inside Harvard's Mark II computer in 1947
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 first 'computer bug' was a literal moth. Found inside Harvard's Mark II in 1947 and taped into the logbook with the note: 'First actual case of bug being found.' 🪲💻 #OddlyHuman”