1.1 Why is testing necessary
• False-fail result : A test result in which a defect is reported although no such defect
actually exists in the test object
• Error (mistake) : A human action that produces an incorrect result
• Failure : deviation of the component of system from its expected delivery, service of
result
• Defect (bug, fault) : A flaw in a component or system that can cause the component or
system to fail e.g. an incorrect statement or data definition