Functional testing: It is testing the ‘functionality’ of a software or an application under test. It tests the behavior of the software under test. Based on the requirement of the client, a document called a software specification or requirement specification is used as a guide to test the application.
Non-functional testing: In software terms, when an application works as per the user’s expectation, smoothly and efficiently under any condition, then it is stated as a reliable application. Based on quality, it is very critical to test these parameters. This type of testing is called non-functional testing.