"Jon A. Cruz" wrote:
> 
> Ken wrote:
> 
> > A bug is a design problem in the program. A bug can cause the program
> > to crash or return the wrong results when a specific feature is used.
> 
> Would it perhaps be more accurate to say that a bug is a problem in the
> implementation of the program. That is, the design itself (what was intended) may
> be OK, but there might be a problem when you actually go to write the code that's
> supposed to perform the designed function.

bug n. An unwanted and unintended property of a program or piece of hardware, esp.
one that causes it to malfunction. Antonym of feature. Examples: "There's a bug
in the editor: it writes things out backwards." "The system crashed because of a
hardware bug." "Fred is a winner, but he has a few bugs" (i.e., Fred is a good guy,
but he has a few personality problems).

Historical note: 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!

Or perhaps not a joke. Historians of the field inform us that the term "bug" was
regularly used in the early days of telegraphy to refer to a variety of semi-
automatic telegraphy keyers that would send a string of dots if you held them down.
In fact, the Vibroplex keyers (which were among the most common of this type) even
had a graphic of a beetle on them (and still do)! While the ability to send repeated
dots automatically was very useful for professional morse code operators, these were
also significantly trickier to use than the older manual keyers, and it could take
some practice to ensure one didn't introduce extraneous dots into the code by holding
the key down a fraction too long. In the hands of an inexperienced operator, a
Vibroplex "bug" on the line could mean that a lot of garbled Morse would soon be
coming your way.

Further, the term "bug" has long been used among radio technicians to describe a
device that converts electromagnetic field variations into acoustic signals. It is
used to trace radio interference and look for dangerous radio emissions. Radio
community usage derives from the roach-like shape of the first versions used by
19th century physicists. The first versions consisted of a coil of wire (roach body),
with the two wire ends sticking out and bent back to nearly touch forming a spark
gap (roach antennae). The bug is to the radio technician what the stethoscope is
to the stereotype medical doctor. This sense is almost certainly ancestral to modern
use of "bug" for a covert monitoring device, but may also have contributed to the
use of "bug" for the effects of radio interference itself.

Actually, use of `bug' in the general sense of a disruptive event goes back to
 Shakespeare! (Henry VI, part III - Act V, Scene II: King Edward: "So, lie thou
there. Die thou; and die our fear; For Warwick was a bug that fear'd us all.")
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 role-playing games.

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."

A careful discussion of the etymological issues can be found in a paper by Fred R.
Shapiro, 1987, "Entomology of the Computer Bug: History and Folklore", American
Speech 62(4):376-378.

[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 was not actually exhibited years afterwards. Thus, the process
of investigating the original-computer-bug bug fixed it in an entirely unexpected
way, by making the myth true! --ESR]


-- 
Ken Tyler

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