Bug (engineering)

In engineering, a bug is a defect in the design, manufacture or operation of machinery, circuitry, electronics, hardware, or software that produces undesired results or impedes operation. It is contrasted with a glitch which may only be transient. Sometimes what might be seen as unintended or defective operation can be seen as a feature. The Middle English word bugge is the basis for the terms "bugbear" and "bugaboo" as terms used for a monster. The term "bug" to describe defects has been a part of engineering jargon since the 1870s and predates electronic computers and computer software; it may have originally been used in hardware engineering to describe mechanical malfunctions. For instance, Thomas Edison wrote the following words in a letter to an associate in 1878: It has been just so in all of my inventions. The first step is an intuition, and comes with a burst, then difficulties arise—this thing gives out and [it is] then that "Bugs"—as such little faults and difficulties are called—show themselves and months of intense watching, study and labor are requisite before commercial success or failure is certainly reached. This shows that using the word bugs was already widespread by 1870s. In a comic strip printed in a 1924 telephone industry journal, a naive character hears that a man has a job as a "bug hunter" and gives a gift of a backscratcher. The man replies "don't you know that a 'bug hunter' is just a nickname for a repairman?" Baffle Ball, the first mechanical pinball game, was advertised as being "free of bugs" in 1931. Problems with military gear during World War II were referred to as bugs (or glitches). In the 1940 film, Flight Command, a defect in a piece of direction-finding gear is called a "bug". In a book published in 1942, Louise Dickinson Rich, speaking of a powered ice cutting machine, said, "Ice sawing was suspended until the creator could be brought in to take the bugs out of his darling." Isaac Asimov used the term "bug" to relate to issues with a robot in his short story "Catch That Rabbit", published in 1944.