Black box

• A black box is a system whose input and output characteristics are well understood, but one has no idea what is going on inside. There are several main senses:
  • In electronics, a sealed piece of replaceable equipment - see line-replaceable unit.
  • In computer programming and software engineering, black box testing is used to check that the output of a program is as expected given certain inputs. The term black box is used because the actual program being executed is not examined.
  • In philosophy and mathematics - see black box theory.

• The term has several other senses:
  • In aircraft, the flight data recorders and cockpit voice recorders, that record aircraft and pilot behavior in order to analyze accidents are called "black boxes" by the news media. (Even though they are now bright orange in colour, they were black when originally introduced.)
  • Black Box is a board and computer game.
  • Black Box was a music group popular in the early 1990s
  • Black Box Recorder was a music group, popular in the early 2000s.
  • In literature, Black Box is a book by Israeli writer Amos Oz.
  • Phone Phreaking, the black box was a device built by phone phreaks during the 1960s and 1970s to defeat toll charges.
  • Black box theater.
  • Blackbox is a window manager that works on X Window System platforms.