As far back as the 1870s, Thomas Edison was using the word “bug” to refer to a flaw in the design or operation of a system. But it wasn’t until the next century—and with a piece of equipment destined for Dahlgren—that a popular phrase sprouted wings.
That term was “computer bug,” and it was coined Sept. 9, 1947, at Harvard University as scientists and technicians worked on an early, gigantic computer known as the Mark II, or Aiken Relay Calculator.
Harvard had formed a partnership with the Navy base at Dahlgren, which eventually would use the machine—after it had been thoroughly vetted—to handle all the computational work needed to test Navy guns, unguided rockets and bombs.
As Harvard officials ran simulations on that September day, two years after the end of World War II, there was a problem. Some might call it a fly in the ointment. Or say that an insect literally floated like a butterfly into one of the computer’s relays and stung like a bee when it started causing all kinds of malfunctions.
Technician Bill Burke traced the error to a moth—drawn not by a flame, but by the massive amount of heat the mainframes generated. Burke removed the moth, did more tests and determined the computer was working again. He taped the insect into the daily computer maintenance log, noting he had removed the moth from the relay.
“From that time on, the engineers and technicians referred to finding and removing a fault in the computer or a program as ‘debugging.’ This ‘bug’ is widely credited as being the original computer bug,” said Ray Hughey, a Dahlgrenite who shared the story with The Free Lance–Star in 2012.
The story about the moth grew in almost mythical proportions from the 1947 discovery. Grace M. Hopper, who was associated with Aiken at Harvard and ended up as a rear admiral in the Navy, told the story of the “bug” many times over the years. Some of her audiences eventually got the impression that she had discovered the “bug,” and in subsequent years, people set out to debunk the myth.
Even Ken Jennings, considered the ultimate “Jeopardy!” champion in some circles, wrote in 2016 that while Hopper was one of the greatest computer pioneers of the 20th century—people often referred to her as “Amazing Grace”—she wasn’t responsible for coining the phrases “bug” or “debugging.” Both already were in existence long before the moth made its presence known, he said.
Some of that may be nitpicking, as in the painstaking removal of tiny parasitic nits (lice or lice eggs) from someone’s hair. In a 2012 column, Ed Jones, former Free Lance–Star editor and president of the Dahlgren Heritage Foundation, acknowledged that embellishments had been made to the tale over time, but said, “There’s still enough truth to this story to make it one of the most fascinating footnotes in Dahlgren history.”
The folks at Dahlgren are so enchanted by the moth that they have asked the Smithsonian Institution if it will loan them the bug and computer log for a temporary display at the Dahlgren Heritage Museum.
Dahlgren officials gave the bug to the Smithsonian in 1993 after it became apparent the moth was becoming extremely fragile and was in danger of “being lost forever,” Hughey said in 2012.
Guess no one ever heard of mothballs?