<programming> An unwanted and unintended property of a program or piece
of hardware, especially one that causes it to malfunction. Antonym of feature.
E.g. "There's a bug in the editor: it writes things out backward." The
identification and removal of bugs in a program is called "debugging".
Admiral Grace Hopper (an early computing pioneer better known for inventing
COBOL) liked to tell a story in which a technician solved a glitch in the
Harvard Mark II machine by pulling an actual insect out from between the
contacts of one of its relays, and she subsequently promulgated bug in its
hackish sense as a joke about the incident (though, as she was careful to admit,
she was not there when it happened). For many years the logbook associated with
the incident and the actual bug in question (a moth) sat in a display case at
the Naval Surface Warfare Center (NSWC). The entire story, with a picture of the
logbook and the moth taped into it, is recorded in the "Annals of the History of
Computing", Vol. 3, No. 3 (July 1981), pp. 285--286.
The text of the log entry (from September 9, 1947), reads "1545 Relay #70 Panel
F (moth) in relay. First actual case of bug being found". This wording
establishes that the term was already in use at the time in its current specific
sense - and Hopper herself reports that the term "bug" was regularly applied to
problems in radar electronics during WWII.
Indeed, the use of "bug" to mean an industrial defect was already established in
Thomas Edison's time, and a more specific and rather modern use can be found in
an electrical handbook from 1896 ("Hawkin's New Catechism of Electricity", Theo.
Audel & Co.) which says: "The term "bug" is used to a limited extent to
designate any fault or trouble in the connections or working of electric
apparatus." It further notes that the term is "said to have originated in
quadruplex telegraphy and have been transferred to all electric apparatus."
The latter observation may explain a common folk etymology of the term; that it
came from telephone company usage, in which "bugs in a telephone cable" were
blamed for noisy lines. Though this derivation seems to be mistaken, it may well
be a distorted memory of a joke first current among *telegraph* operators more
than a century ago!
Actually, use of "bug" in the general sense of a disruptive event goes back to
Shakespeare! In the first edition of Samuel Johnson's dictionary one meaning of
"bug" is "A frightful object; a walking spectre"; this is traced to "bugbear", a
Welsh term for a variety of mythological monster which (to complete the circle)
has recently been reintroduced into the popular lexicon through fantasy
In any case, in jargon the word almost never refers to insects. Here is a
plausible conversation that never actually happened:
"There is a bug in this ant farm!"
"What do you mean? I don't see any ants in it."
"That's the bug."
[There has been a widespread myth that the original bug was moved to the
Smithsonian, and an earlier version of this entry so asserted. A correspondent
who thought to check discovered that the bug was not there. While investigating
this in late 1990, your editor discovered that the NSWC still had the bug, but
had unsuccessfully tried to get the Smithsonian to accept it - and that the
present curator of their History of American Technology Museum didn't know this
and agreed that it would make a worthwhile exhibit. It was moved to the
Smithsonian in mid-1991, but due to space and money constraints has not yet been
exhibited. Thus, the process of investigating the original-computer-bug bug
fixed it in an entirely unexpected way, by making the myth true! - ESR]
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