Bit bucket

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This article is about the bit bucket in computing. For other uses, see black hole (disambiguation).
Not to be confused with the source code hosting service Bitbucket.
The chip receiver (or "bit bucket") from a UNIVAC key punch

In computing jargon, the bit bucket is where lost computerized data has gone, by any means; any data which does not end up where it is supposed to, being lost in transmission, a computer crash, or the like, is said to have gone to the bit bucket — that mysterious place on a computer where lost data goes, as in:

The errant byte, having failed the parity test, is unceremoniously dumped into the bit bucket, the computer's wastepaper basket.

— Erik Sandberg-Diment, New York Times, July 9, 1985[1]

Millions of dollars in time and research data gone into the bit-bucket?

— W. Paul Blase, The Washington Post, Feb. 17, 1990[2]

Originally, the bit bucket was the container on Teletype machines or IBM key punch machines into which chad from the paper tape punch or card punch was deposited;[3] the formal name is "chad box" or (at IBM) "chip box".

The term was then generalized into any place where useless bits go, a useful computing concept known as the null device. The term bit bucket is also used in discussions of bit shift operations.[4]

Such a device is sometimes referred to as a "write once read never" or WORN device (named after the magneto-optical WORM devices used during the 1980s). The WORN device is related to the First In Never Out stack and Write Only Memory, in a joke datasheet issued by Signetics in 1972. Atari implemented a WORN device as an Easter Egg in the operating system for the Atari 800, something revealed by Atari BASIC author Bill Wilkinson in a 1988 April Fool's article in Compute! magazine.[5]

In programming languages the term is used to denote a bitstream which does not consume any computer resources, such as CPU or memory, by discarding any data "written" to it. In .NET Framework-based languages, it is the System.IO.Stream.Null.[6]

See also[edit]


  1. ^ Sandberg-Diment, Erik (July 9, 1985). "Parity: An Elegantly Simple Approach to Errors". New York Times. New York, N.Y.: New York Times Company. Retrieved 8 November 2013. 
  2. ^ Blase, W. Paul (Feb 17, 1990). "No Harmless Hacker He". The Washington Post. Washington, D.C.: The Washington Post Company. Retrieved 8 November 2013. 
  3. ^ Cutler, Donald I. (1964). Introduction to Computer Programming. Prentice-Hall. p. 108. Retrieved 8 November 2013. The lost bits fall into a container called a bit bucket. They are emptied periodically and the collected bits are used for confetti at weddings, parties, and other festive occasions. 
  4. ^ O'Brien, Frank (2010). The Apollo Guidance Computer: Architecture and Operation. Springer. p. 45. ISBN 9781441908773. Retrieved 8 November 2013. 
  5. ^
  6. ^ "Using null stream as bit bucket" — an article on C# at

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