Difference and Application of White-Box, Black-Box, and Grey-Box Testing

In this paper, we explore key differences and practical applications of white-box, black-box, and grey-box testing methodologies in software development. Through theoretical comparison and real-world implementation on a test project, we demonstrate how each method serves a unique role in ensuring software quality. Testing is conducted on a web application developed with React Native and Supabase as the backend, where users can post and manage personal comments. This app serves as a case study for applying each testing approach. White-box testing was used to verify internal logic and data handling. Black-box testing evaluated user-facing features, such as comment posting. Grey-box testing combined knowledge of both to assess security and integration with the backend. This paper aims to clarify when and why each testing type should be used, particularly in small-scale projects as the one used as a test case. This serves as a practical guide for students and developers to understand and apply testing strategies more effectively in their own applications. Grey-Box, White-Box, Black-Box