Editing Regression testing (section)

== Benefits and drawbacks ==
Regression testing is performed when changes are made to the existing functionality of the software or if there is a bug fix in the software. Regression testing can be achieved through multiple approaches; if a ''test all'' approach is followed, it provides certainty that the changes made to the software have not affected the existing functionalities, which are unaltered.<ref name=":1">{{cite journal |last1=Yoo |first1=S. |last2=Harman |first2=M. |title=Regression testing minimization, selection and prioritization: a survey |journal=Software Testing, Verification and Reliability |date=2010 |volume=22 |issue=2 |pages=67–120|doi=10.1002/stvr.430}}</ref>

In [[agile software development]]—where the software development life cycles are very short, resources are scarce, and changes to the software are very frequent—regression testing might introduce a lot of unnecessary [[Overhead (business)|overhead]].<ref name=":1" />

In a software development environment which tends to use [[black box]] components from a third party, performing regression testing can be tricky, as any change in the third-party component may interfere with the rest of the system (and performing regression testing on a third-party component is difficult, because it is an unknown entity).<ref name=":1" />