Our purpose of functional tests is to test each function of the software application repeatedly, by providing appropriate input, verifying the output against the functional requirements.
During functional testing, Black Box Testing technique is used in which the internal logic of the system being tested is not known to the tester.
Functional testing involves the following steps:
Identify functions that the software is expected to perform.
Create input data based on the function’s specifications.
Determine the output based on the function’s specifications.
Execute the test case.
Compare the actual and expected outputs.
We basically focus on checking of users interface, APIs, database, security, client or server application and functionality of the Application Under Test.