Boîte noire. Black box theory. Black box theories are things defined only in terms of their function. The term black box theory is applied to any field, philosophy and science or otherwise where some inquiry or definition is made into the relations between the appearance of something (exterior/outside), i.e. here specifically the things black box state, related to its characteristics and behaviour within (interior/inner). Specifically, the inquiry is focused upon a thing that has no immediately apparent characteristics and therefore has only factors for consideration held within itself hidden from immediate observation.
The observer is assumed ignorant in the first instance as the majority of available data is held in an inner situation away from facile investigations. The black box element of the definition is shown as being characterised by a system where observable elements enter a perhaps imaginary box with a set of different outputs emerging which are also observable. Origin of term Black-box testing. Black box diagram Black-box testing is a method of software testing that examines the functionality of an application (e.g. what the software does) without peering into its internal structures or workings (see white-box testing).
This method of test can be applied to virtually every level of software testing: unit, integration, system and acceptance. It typically comprises most if not all higher level testing, but can also dominate unit testing as well.