Bug
From The Glossary of Digital Photography
An error in a computer software program. The term came into being on September 9, 1945, at 3:45 p.m. at the Harvard Computation Laboratory when Lieutenant, Junior Grade Grace M. Hopper, later a rear admiral, traced a problem the laboratory was having with the Mark II computer to a moth that had gotten caught between two relays. Laboratory technicians removed the moth and taped it into their log book (which is why we can date the expression so precisely). The computer began operating properly once again. Ever since then, a computer or a piece of software that is not operating properly is said to have a bug in it.
