How does smoke testing differ from regression testing?

Smoke testing is a superficial check of the main functions of an application to ensure that the system launches and key scenarios work. It is usually performed after build or deployment to quickly identify critical errors.

Regression testing is a more in-depth and comprehensive testing aimed at verifying that new changes have not broken existing functionality. It involves re-executing a set of test cases.

Key differences:

• Smoke tests are quick and superficial, while regression tests are more thorough and longer.
• Smoke tests check basic operability, regression tests check stability after changes.

Example: after updating the application, a smoke test is run to verify that it launches and the main functions are accessible. If the smoke test passes, regression testing is performed to verify all important scenarios.