Brief Description About Grey Box Testing

Grey box testing is a method in which an application can be tested with partial knowledge of internal working of any application. It is a testing method which is the combination of White box and Black box testing.
For white box testing, one should know the code 
For black box testing, there is no need to know the programming language
For grey box testing,  the code is partially known
With grey box testing, the tester can test both sides of the application i.e user interface and code.

Reason to perform Grey box testing:
1. It gives the benefit of the Black box and White box testing
2. It gives ample time to developers to fix the defects
3. It gives the combined input of developers and testers to improve the performance of the application
4. Testing is done from an end-user perspective, not from the designer perspective

Techniques used for Grey box testing:
Matrix Testing: In this techniques, the tester will define all the variables in the program
Regression Testing: This testing is done to test whether a change in one feature will not cause a defect in the tested feature. Testing strategy for this technique will be retest all, retest risky use case etc.
Orthogonal array testing: Maximum code coverage can be done using this technique
Steps to perform Grey box testing:
Step1: Identifying the input
Step2: Identifying the output
Step3: Identifying the major paths
Step4: Identifying the Subfunctions
Step5: Develop inputs for Subfunctions
Step6: Develop output for Subfunctions
Step7: Execute test case for Subfunctions
Step8: Verify correct result for Subfunctions
Step9: Repeat step 4 to 8 for other Subfunctions

Tools used to perform grey box testing:
Selenium
Appium
Rational Functional Tester
Chrome Dev Tools

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