In September 1947, engineers at Harvard pulled a moth from a relay inside the Mark II computer, taped it into the logbook, and wrote ‘first actual case of bug being found’ — the pest was literal
The famous moth taped into a Harvard logbook in 1947 is often called the birth of the word “bug” in computing. The truth is stranger and older — the engineers were making a joke that only worked because the term already had decades of history.