See black box testing
and Black Box Corporation
An electronic device that records airplane flight data. Officially a "flight data recorder," the unit is highly protected and can emit a signal for up to 30 days after a crash, even underwater. First used in the late 1950s, Australia was the first country to require them. Dating back to the late 19th century, a "train event recorder" or "on-train monitoring recorder" (OTMR) is the equivalent device in a locomotive.
An electronic device that records driving data in motor vehicles, most notably their speed. Officially an "event data recorder," automotive black boxes were first used in the late 1990s.
Any custom-made electronic device can be called a black box, typically made to solve some interfacing problem. Such devices were named black boxes because they were often housed in plain containers, and their purpose may even be a mystery to the experienced observer. However, yesterday's black boxes sometimes become today's off-the-shelf products. See COTS
The Black Box
Without logos or identifying marks, a black box can be any device custom made to solve a problem.
A Little Black Box
The 10-ounce device lying on top of this CD changer is an Apple TV set-top box. See Apple TV