Moth in Relay

In 1947 a moth was found in a relay switch on the Mark II electromechanical computer, a true computer "bug." What's most interesting here isn't that an insect was found in the machine, but that the computer operator taped the moth into the logbook. It's almost as if the moth was trapped in a thin sheet of amber, preserved as the pre-digital ancestor of the tricksters within our own modern devices. 

Photo of a moth taped in a log book.

The insect was found by Grace Hopper (Wayback Machine link), a computer scientist and rear admiral in the US Navy. Google recently paid homage to Hopper with a "doodle" (below) showing her working on an early mainframe computer. Not only does the computer display an answer on a paper printout, but a moth also flies out at the end of the sequence.

Google Doodle showing Grace Hopper at a mainframe computer.

(Revised and republished April 19th, 2025)