Spotting bugs in software and debugging them are standard practices in software development these days. However, the terms ‘bug’ and ‘debug’ became popular only after an incident in 1947, even though the term ‘bug’ had been used as far back as in the 1870s by none other than Thomas Alva Edison, and was used by engineers to describe problems that occurred in machines, and even computers.


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In August 1947, Grace Hopper of the US navy and some colleagues were working on the Mark II computer (considered by many to be the grand dad of modern computers) when they found that something was amiss with one of the circuits, causing the computer to malfunction.

They searched and searched and then found the problem – a two-inch moth that was stuck in the circuits. They removed the moth using tweezers, pasted it in their logbook and claimed that it was the first actual case of a bug being found in a computer. They also claimed that by removing it, they had successfully ‘debugged’ the computer! The incident made the two terms famous. In case you are wondering what happened to the moth that was in the logbook, well, it can be seen in the National Museum of American History and can be viewed online at (picture courtesy)

News Reporter