What is the difference between unit testing and functional testing in automation testing?

Difference between Unit Testing and Functional Testing in Automation Testing

Unit testing and functional testing are two fundamental types of automated testing used in software development. Here are the key differences between the two:

Unit Testing:

• Unit testing involves testing individual components or modules of the software in isolation.
• It is typically performed by developers during the development phase.
• Unit testing focuses on verifying the correctness of the code at a unit level.
• Mock objects and stubs are commonly used in unit testing to isolate the code being tested.
• Unit tests are usually faster to execute and provide immediate feedback to developers.

Functional Testing:

• Functional testing involves testing the entire application or system from end-to-end.
• It is typically performed by QA engineers or automation testers during the testing phase.
• Functional testing focuses on verifying that the software meets the specified requirements and functions as expected.
• Integration testing, regression testing, and system testing are all forms of functional testing.
• Functional tests are slower to execute compared to unit tests but provide a higher level of assurance that the software functions correctly.

In summary, unit testing focuses on testing individual units of code, while functional testing verifies the overall functionality of the software. Both types of testing play a crucial role in ensuring the quality and reliability of the software product.