Definations

• Failure → the inability of a system or component to perform a required function according to its specification.

• Fault/Bug → a condition that in actual causes a system to produce failure. Failures are manifestation of bugs.

  Some bugs are hidden in the sense that these are not executed, as they do not get the required conditions in the system.

• Error → Whenever a development team member makes a mistake in any phase of SDLC, errors are produced. Error → Bug → Failure

• TestCase → Test case is a well-documented procedure designed to test the functionality of a feature in the system.

• Testware → The documents created during testing activities

• Incident → An incident is the symptom(s) associated with a failure that alerts the user about the occurrence of a failure.

• Test Oracle → An oracle is the means to judge the success or failure of a test.

Life Cycle of a Bug

Bugs-In Phase → This phase is where the errors and bugs are introduced in the software.

Bugs-Out Phase → If failures occur while testing a software product, we come to the conclusion that it is affected by bugs.

1. Bug Classification - This is necessary, because there may be many bugs to be resolved. But a tester may not have sufficient time.
2. Bug Isolation - activity by which we locate the module in which the bug appears.
3. Bug Resolution - Once we have isolated the bug, we back-trace the design to pinpoint the location of the error.

States of a Bug

<aside> 💡 If the priority of the reported bug is not high or there is not sufficient time to test it or the bug does not have any adverse effect on the software, then the bug is changed to deferred state which implies the bug is expected to be fixed in next releases.

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<aside> 💡 Requirement specification and design phases contain the largest percentage of bugs.

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