What is Black Box Testing?
Black box testing takes an external perspective of the test object to derive test cases. These tests can be functional or non-functional, though usually functional. The test designer selects valid and invalid input and determines the correct output. There is no knowledge of the test object’s internal structure.
Black Box Testing is also known as functional testing. This is a software testing technique whereby the internal workings of the item being tested are not known by the tester. For example, in a black box test on software design the tester only knows the inputs and what the expected outcomes should be and not how the program arrives at those outputs. The tester does not ever examine the programming code and does not need any further knowledge of the program other than its specifications.
Black Box Testing, also known as Behavioral Testing, is a software testing method in which the internal structure/design/implementation of the item being tested is not known to the tester. These tests can be functional or non-functional, though usually functional.
This method is used to find errors in the following cases:
- Incorrect or missing functions
- Interface errors
- Errors in data structures or external database access
- Behavior or performance errors
- Initialization and termination errors
Black Box Testing Advantages:
- Tests are done from a user’s point of view and will help in exposing discrepancies in the specifications
- Tester need not to know programming languages or how the software has been implemented
- Tests can be conducted by a body independent from the developers, allowing for an objective perspective and the avoidance of developer-bias
- Test cases can be designed as soon as the specifications are complete
Black Box Testing Disadvantages:
- Only a small number of possible inputs can be tested and many program paths will be left untested
- Without clear specifications, which is the situation in many projects, test cases will be difficult to design
- Tests can be redundant if the software designer/ developer has already run a test case