"Black box" testing tests a device, program, application, etc., as a whole. Inputs are provided and the results monitored. The internal workings of the tested item are not relevant and may be unknown. "Functional testing" is a type of "Black box testing", but not all "black box" tests have to be "functional".
Black box testing tests a device, program, application, etc., as a whole.
Inputs are provided and the output results monitored. The internal workings of the tested item are not relevant and may be unknown.
Black box testing and Functional testing are sometimes used synonymously, but Functional testing is really a subset. "Non functional" tests, like Stress testing are often done in a "black box" manner.
Compare and contrast to Unit testing and White box testing.
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