[very common] Another widely used
metasyntactic variable; see foo for etymology.
Probably originally propagated through DECsystem manuals by Digital
Equipment Corporation (DEC) in 1960s and early
1970s; confirmed sightings there go back to 1972. Hackers do
not generally use this to mean
FUBAR in either the slang or jargon sense. See also
Fred Foobar. In RFC1639, FOOBAR
was
made an abbreviation for FTP Operation Over Big Address
Records
, but this was an obvious backronym.
It has been plausibly suggested that foobar
spread among
early computer engineers partly because of FUBAR and partly because
foo bar
parses in electronics techspeak as an inverted foo
signal; if a digital signal is active low (so a negative or zero-voltage
condition represents a "1") then a horizontal bar is commonly placed over
the signal label.