Error, Defect, Fault, Bug and failure

Error, Defect, Fault, Bug and failure

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Most of these terms – error, defect, fault, failure, and bugs are used interchangeably but there is a difference between them. Some of these terms are very much different from others.

Error

An error is a mistake made by a human that leads to a discrepancy between the actual and the expected result.

Defect

A defect is a problem in the functioning of a software system during testing.¬†ISTQB¬†defines a defect as “A flaw in a component or system that can cause the component or system to fail to perform its required function, e.g., an incorrect statement or data definition.”

Fault

A fault is an incorrect step, process, or data definition in a software product.

Bug

A bug is a flaw in a software system that causes the system to behave in an unintended manner.

Failure

A failure is the inability of a software system to perform its operations within the specified performance benchmark. As per ISTQB, “a defect, if encountered during execution, may cause a failure of the component or system”.

So, we can say that a mistake made by humans during coding is called an error, an error found during the testing phase is called a defect, a defect to be resolved by the development team is called a bug and when a build does not meet its specifications then it is termed as failure.

More Difference Between

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White-box vs Black-box TestingSystem vs Integration Testing
Verification vs ValidationQuality Assurance vs Quality Control
SDLC vs STLCTest Plan vs Test Strategy
Test Case vs Test ScenarioAgile vs Waterfall Model
Agile vs Scrum MethodologyREST vs SOAP Web Service
Web Application vs Desktop ApplicationWeb Service vs Website
Assert vs VerifyError, Defect, Fault, Failure & Bug

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