black boxes

Black boxes are systems whose internal workings are hidden or unknown—you see inputs and outputs but not the process between.

The term comes from engineering, where components are analyzed purely by their behavior.

Aircraft flight recorders are called black boxes (though typically orange) because investigators examine their data without needing to understand their circuitry.

In computing and AI, black box describes algorithms that produce results through opaque processes: The neural network is a black box—we can't explain why it made that decision.