Grey-Box Testing is a software testing method that combines elements of both black and white box testing.  

Testers have partial knowledge of the system’s internal structure while evaluating its external behavior.  

This approach helps identify logical errors, security flaws, and integration issues within applications.  

It balances developer insight and user perspective, offering a more thorough and efficient testing process.  

Grey-Box Testing often uses tools, code review, and functional tests to ensure reliability and performance.  

It is commonly applied to web apps, APIs, and software systems that require layered verification methods.  

By combining structure awareness with user level testing, it uncovers deeper hidden bugs and weaknesses.  

Grey-Box Testing delivers higher quality assurance, blending precision, functionality, and real user logic.