TestFort published a blog (https://testfort.com/blog/difference-between-black-box-white-box-and-grey-box-testing#:~:text=While%20black%2Dbox%20testers%20make,in%20a%20non%2Dintrusive%20manner.) that does a great job breaking down each black-box, gray-box, and white/clear-box testing. By understanding each one individually, you can clearly see the differences between them. The blog also provides two other useful pieces of information for each of the software testing methods. Those being the most common design techniques and pros and cons.
Black Box Testing:
Testing is done by an independent team that has no knowledge of the code. The purpose of this testing method is to test the user interface’s functionality and usability. This testing method uses the users point of view to test the expected behaviors of the application.
The first example of black box testing that comes to mind is video-game testing. Testers are often given a demo of a game to play and give feedback on. These testers have no knowledge of the game’s code, however by playing the game they are testing for bugs and evaluating the user interface.
White/Clear Box Testing:
Testing is done by developers that have a great understanding of the application’s internal structure. This testing method’s purpose is to test and analyze that internal structure and its logic using the developers point of view. Developers commonly use tools to help analyze and debug code.
As I am only beginning my journey into developing tests I don’t have much experience with using debugging tools outside of ones provided inside some video games. However, when developing my own code I would commonly add print statements to verify variable values in the middle of the code. This would typically help me catch when values were being assigned incorrectly, scope issues, or simple off-by-one errors.
Gray Box Testing:
Testing can be done by developers, testers, and users with a similar testing approach as black box testing. Test cases are designed by an engineer that has decent knowledge of the internal structures. These test cases provide the testers with a glimpse into the software’s architecture without direct access to the source code. This form of testing aims to find defects and vulnerabilities in the structure of the code while combining the advantages of both black and white box testing.
This testing method is the one I have the least experience in, and is therefore the hardest for me to fully understand. My current understanding from this blog is relating it to when I would test software in the military. For obvious reasons, source code was hidden, however the functionality of each feature was documented so that testers could have a clear understanding of what the software was doing.
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