Well SrIM .... To me Black BOX is some what a broader term and functional testing is a part of it.
its not wrong to say that "Black Box testing is not a type of testing" Its a testing strategy and to implement that strategy we have the testing types as functional testing, Alpha beta testing, boundary value, smoke testing analysis etc etc
Black BOX is a testing strategy that contains both functional and non-functional testing.
Functional testing to test the core functionality what are the data inputs, what will be outputs.
Non functional as to test the reliability,scalability, run time performance etc
thats what i think i hope you agree to this too...;)
Here's an example from real testing: Security testing can be done at black box, but it is non-functional testing. So black box is wider than functional testing as previous people mentioned. SriM, do you need more examples or more detailed description why it is non-functional but can be black box?
I guess this should be enough to understand on Diff b/w Functional testing & Black box testing...
**Functional testing is a sub-category of black box testing. Thus black box testing is a generic term and functional testing is more specialized term.
Black box testing is conducted in the external part of the application or check the funtionality of the application
Other kinds of tests under black box testing are, load testing, peformance testing, Regression,Re-testing and so on.
You cannot compare Black Box with Functional Testing. The both belong to different class i.e.
Black Box is a Testing STRATEGY wthich covers lot of testing types.
Functional Testing is a TYPE of testing which comes unnder the umbrella of Black Box.