White Box Testing is a software testing method that examines the internal structures or workings of an application. Testers have access to the source code and can design test cases based on the code's logic, algorithms, and control flow. This approach helps identify hidden errors and ensures that all code paths are tested. By focusing on the internal components, White Box Testing allows for thorough validation of the software's functionality. It is often used in conjunction with other testing methods, such as Black Box Testing, to provide a comprehensive assessment of the software's performance and reliability.