What is the difference between 'black-box testing' and 'white-box testing'?

The distinction between black-box testing and white-box testing is fundamentally rooted in their approach and perspective towards the software being tested.

Black-box testing is characterized by its focus on the functionality of an application without any consideration of internal code structure or logic. Testers approach the software purely based on requirements and specifications, concentrating on inputs and expected outputs. This method assesses how the software behaves against the defined criteria, without delving into how those functionalities are implemented in the code. By testing in this manner, black-box testing embodies the principle of understanding user behavior and functional requirements.

On the other hand, white-box testing is rooted in an understanding of the internal workings of the application. Testers leverage their knowledge of the codebase, requiring familiarity with the code structure, algorithms, and logic to design their test cases. This enables them to directly assess the internal mechanisms of the software, ensuring that the code performs as expected in terms of logic coverage, path coverage, and other structural testing techniques.

Therefore, the correct choice captures the essence of these methodologies: black-box testing is input and output-centric while white-box testing necessitates insight into the code itself. This fundamental difference governs how each testing method is applied in practice, defining their uses, advantages, and typically, the