Error Handling: Error handling is a mechanism in programming that deals with anticipated errors during runtime. It allows developers to handle exceptions gracefully rather than causing program crashes.
Regression Testing: Regression testing is retesting modified parts of software systems after modifications have been made to ensure that previously working functionality has not been affected by the changes.
Unit Testing: Unit testing is a software testing method where individual components or units of code are tested to verify their proper functionality in isolation from the rest of the system.