Common types of testing in software development include unit testing, integration testing, system testing, and user acceptance testing (UAT). Unit testing focuses on individual components to ensure they function correctly in isolation. Integration testing examines how different components work together, while system testing evaluates the complete system to verify that it meets specified requirements. UAT involves end users to validate that the software meets their needs before deployment. Implementing these testing types throughout the development lifecycle helps identify defects early, ensuring the quality and reliability of the final product.