Test Execution is the phase of the Software Testing Life Cycle (STLC) where the QA team executes the prepared test cases on the application under test (AUT) to verify whether the software behaves as expected.

It involves:

• Running the test cases manually or using automation tools.
• Comparing actual results with expected results.
• Reporting defects/bugs if mismatches occur.
• Retesting and regression testing after fixes.