What is the purpose of test cases in software testing?

The purpose of test cases in software testing is to systematically and thoroughly evaluate the functionality, performance, and reliability of a software application. Test cases are designed to verify whether the software meets the specified requirements and to identify any defects or issues that may exist.

Test cases serve several important purposes in the software testing process:

1. Verification of Requirements: Test cases are created based on the software requirements and specifications. They are used to validate that the software functions as intended and meets the defined requirements. By executing test cases, testers can ensure that all the expected functionalities are implemented correctly.

2. Defect Identification: Test cases are designed to uncover defects or bugs in the software. By executing various test scenarios, testers can identify any deviations from the expected behavior and report them as defects. This helps in improving the quality of the software by identifying and fixing issues before the software is released to the end-users.

3. Coverage Analysis: Test cases help in analyzing the coverage of the software testing process. By creating a comprehensive set of test cases, testers can ensure that all the critical functionalities and scenarios are tested. This helps in minimizing the risk of undiscovered defects and ensures that the software is thoroughly tested.

4. Regression Testing: Test cases are used for regression testing, which is performed to ensure that the changes or modifications made to the software do not introduce new defects or impact the existing functionalities. By re-executing the previously created test cases, testers can verify that the software still functions correctly after any changes are made.

5. Documentation: Test cases serve as documentation for the testing process. They provide a clear and structured approach to testing, making it easier for testers to execute and track the progress of testing activities. Test cases also act as a reference for future testing efforts and can be used to train new testers.

In summary, the purpose of test cases in software testing is to validate the software against the specified requirements, identify defects, ensure comprehensive coverage, perform regression testing, and provide documentation for the testing process. Test cases play a crucial role in ensuring the quality and reliability of the software application.