Integration testing

Integration testing focuses on validating the interaction and data flow between integrated units. It's a crucial step after unit testing and before system testing, aiming to detect defects arising from the combined functionality of different modules. Common approaches include top-down (testing from high-level modules to low-level), bottom-up (testing from low-level modules to high-level), and big-bang (integrating all modules simultaneously). Stubs and drivers are often used to simulate missing or incomplete modules during integration. Successful integration testing reduces the risk of system-level failures and ensures the overall software system functions as expected.