What is regression testing and when should it be performed during manual testing?

Regression testing is a type of software testing that focuses on verifying that previously developed and tested software still performs correctly after modifications, bug fixes, or enhancements have been made. It aims to ensure that the changes introduced to the software have not unintentionally affected its existing functionality.

• During manual testing, regression testing should be performed when there are changes made to the software or its environment. It typically follows after a round of functional or non-regression testing, where new features or fixes are tested. Regression testing is crucial because even minor changes in the codebase can introduce unexpected issues or break existing functionality.

         Here are some scenarios when regression testing should be performed during manual testing:

• Bug fixes: After a bug has been identified, fixed, and verified, regression testing ensures that the fix did not introduce new bugs or affect previously working features.

• Software enhancements: When new features or enhancements are added to the software, regression testing ensures that these changes did not adversely impact the existing functionality.

• Configuration changes: If there are changes to the software's configuration settings, regression testing helps ensure that the application continues to function as expected under the new configuration.

• Platform or environment changes: If there are changes to the operating system, browser version, hardware, or any other components of the testing environment, regression testing helps identify any compatibility issues that might have been introduced.

• Integration testing: When integrating different modules or components, regression testing verifies that the integration did not cause any unintended side effects on the overall system.

The frequency of performing regression testing during manual testing depends on the project and its specific requirements. It can be performed after each round of changes or periodically, such as during specific milestones or releases. The goal is to ensure that the software remains stable and functional throughout its lifecycle, even with ongoing development and maintenance activities.