Software testing test suites are basically collection or group or test cases which are created to test the application for specific behavior. for example after regression testing some modules needs to be tested for impacts, to verify this tester asks the list of impacted modules and impacted functionalities to developer, based on their inputs they come up with some sort of test cases to be executed on the application on release of new build.
Creating test suite can improve test coverage and at the same time it will also make testing efforts more structured.
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