Black box testing is a software testing methodology that focuses on the functional requirements of a system without considering its internal workings or implementation details. Therefore, the tester need not have any knowledge of the internal structure or design of the system.
It ensures that a system meets the requirements specified by the customer or user. A black box test can be conducted at different levels, including unit testing, integration testing, and system testing. In order to identify defects and ensure that a system works properly, running black-box tests is a valuable approach.