A black box can referred to as almost anything from a transistor to an algorithm to a human mind. The black box is a device, system, or object which can be view in terms of its input, output, and transfer characteristics without any knowledge of its internal workings. The opposite is a system where the inner components or logic are available for inspection which is sometimes known as a white box, a glass box, or a clear box.
The term “black box” came into the English language around 1945. The ideas for the black box came from Wilhelm Cauer in 1941. Although he didn’t coin the term his methods were described as black-box analysis. There are many different types of black boxes including the electronics version which is a sealed piece of replaceable equipment. In computers, black box testing is used to check that the output of a program is expected. The most common known use of a “black box” is in aviation where an audio recording device is in the cockpit that allows the conversation of pilots during flight to be recorded in case something goes wrong.