Black Box

black box

A custom-made electronic device, such as a protocol converter or encryption system. Yesterday's black boxes often become today's off-the-shelf products. See Black Box Corporation.

The Black Box

A black box does not have to look like a box. It can be any contraption that is custom made for an application.

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black box

1. a self-contained unit in an electronic or computer system whose circuitry need not be known to understand its function

2. an informal name for flight recorder

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black box [′blak ‚bäks]

(engineering)

Any component, usually electronic and having known input and output, that can be readily inserted into or removed from a specific place in a larger system without knowledge of the component's detailed internal structure.

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(jargon)

black box - An abstraction of a device or system in which only its externally visible behaviour is considered and not its implementation or "inner workings". See also functional testing.

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Black Box 

(in Russian, chernyi iashchik), an object of study whose internal structure either is unknown or is too complex for any conclusions about the behavior of the object to be drawn on the basis of the properties of the object’s elements or on the basis of the structure of the connections between the elements. In Russian, the term chernyi iashchik is also used to refer to the method of studying such objects.

The black-box method is used in cases where an outside observer knows only the input to an object and the object’s response; in such cases, the processes occurring within the object are unknown. The study of a multiterminal network whose internal circuitry is unknown provides a very simple example of the use of the black-box method. By observing the behavior of such an object for a sufficiently long time and, if necessary, by carrying out active experiments on the object (that is, by changing the input in some specific manner), a level of knowledge about the properties of the object may be achieved such that changes in the object’s behavior in response to any given input may be predicted. However, no matter how thoroughly the behavior of a black box is studied, an unambiguous conclusion about the internal structure of the object cannot be reached, since the same behavior may be characteristic of different objects.

The black-box method is widely used to solve problems in the modeling of controlled systems—for example, in the study of integrated systems—especially in cases where the behavior rather than the structure of a system is of interest.