Functional Testing
“Functional testing is a type of black box testing. Functional tests are written according to the functional requirements and specifications”
These tests are executed with proper input without knowing the internal program implementation.
Functional testing does not imply that you are testing a function (method) of your module or class. Functional testing tests a slice of functionality of the whole system. It comprises of UI usability, accessibility of the system features to the user, displaying of proper success or error messages to the user.