Black-Box Testing or Behavioural Testing

Contrary to the White-Box Testing, Black-Box Testing examines the functionality of a software program, rather than its internal structure. Another point of differentiation is that, unlike in Glass-Box Testing, the tester only requires knowledge on what the software does.

This type of testing includes-

• Equivalence Partitioning technique: test design technique in which  input data units are divided into into partitions of similar data, from which representative values from partitions are tested.
• Boundary Value Analysis: it involves specifying the boundaries for input values, and testing the selected values that are at and inside/outside the boundaries
• All-Pairs Testing: in this testing method of combinations, all discrete combinations of input parameters are tested.
• Decision Table Testing: In this approach, Decision Tables like flow-charts and switch-case statements are used to associate conditions with actions.
• Cause-Effect Graph: this testing includes identifying input (cases) and output (effects) conditions, producing graph and test cases accordingly.
• Error Guessing: it is a type of software testing in which conditions or variables, that are used to find bugs in software system, are determined based on tester’s intuition and experience in previous testing.

Since Black-box testing deals with the application from the end user perspective, a tester does not examine source codes. As a result, he/she is likely to leave some or most parts of software program unexamined.