Where do computer bugs come from?

We all know the words "bug in the system" or "computer bug". Where does this nifty little phrase come from?

There is apparently an urban legend of sorts which is continuously repeated by zealous people, possibly started by that person in your office who also has a knack for sending out numerous "save a child by sending this message" emails, whereby the origin of the word 'bug' is attributed to a bothersome little insect that was squashed amongst the cogs and wheels of the computer.

Hmm, I changed my previous account - the damn moth really did get caught in the cogs. So it seems. But the word itself in that context was not coined by roadkill moth but rather, had been used earlier, to refer to faults or problems in the machine due to unknown causes.

According to AskOxford, the origins of the word 'bug' (computer bug to you techno-junkies) can be traced to Thomas Edison.

Seems like he might have been referring to the problems in one particular device, stating that it was almost like "some imaginary insect has secreted itself inside and is causing all the trouble".

Now you know. Incidentally, the moth in question is stored in the National Museum of American History of the Smithsonian Institution.

Incidentally, maybe Edison would not have had so many 'bugs' if he had kept Nikola Tesla in his service.