QA Testing Interview Question:

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

Submitted by: Administrator

Black-box and white-box are test design methods. Black-box test design treats the system as a “black-box”, so it doesn't explicitly use knowledge of the internal structure. Black-box test design is usually described as focusing on testing functional requirements. Synonyms for black-box include: behavioral, functional, opaque-box, and closed-box. White-box test design allows one to peek inside the “box”, and it focuses specifically on using internal knowledge of the software to guide the selection of test data. Synonyms for white-box include: structural, glass-box and clear-box.
While black-box and white-box are terms that are still in popular use, many people prefer the terms 'behavioral' and 'structural'. Behavioral test design is slightly different from black-box test design because the use of internal knowledge isn't strictly forbidden, but it's still discouraged. In practice, it hasn't proven useful to use a single test design method. One has to use a mixture of different methods so that they aren't hindered by the limitations of a particular one. Some call this 'gray-box' or 'translucent-box' test design, but others wish we'd stop talking about boxes altogether.
Submitted by: Administrator