Quality is delighting customers
Functional testing involves the complete integration system to evaluate the system’s compliance with its specified requirements. Based on the functional specification document this type of testing is to be carried out. In actual testing, testers need to verify a specific action or function of the code.
Non functional testing has a great influence on customer and user satisfaction with the product. Non functional testing should be expressed in a testable way, not like “the system should be fast” or “the system should be easy to operate” which is not testable.