Functional Testing and Non-Functional Testing.

Functional Testing

• In functional testing, the focus of testing activities is on functional aspects of the system. 
• Test cases are written to check the expected output. 
• Functional testing is normally performed in all the test phases from unit to system testing.

Non-Functional Testing

• In non-functional testing, the focus of the testing activities is on non functional aspects of the system. 
• Non functional testing is normally carried out during the System Testing phase only. 
• The focus of non functional testing is on the behavior and user experience of the system.