FUNCTIONALITY TESTING:
It is a type of testing to test the feature of the product .Whether it covers all its purpose and list of all functionalities and also to check whether it is created as per the requirements from the SRS or BRS document.
Functional testing is also a type of black box testing that holds the test cases based on the specifications of the component under test.
what the system actually does is functional testing. To verify that each function of the software application behaves as specified in the requirement document. Testing all the functionalities by providing appropriate input to verify whether the actual output is matching the expected output or not. It falls within the scope of black box testing and the testers need not concern about the source code of the application.

1. What the system actually does is functional testing
2. To ensure that your product meets customer and business requirements and doesn’t have any major bugs
3. To verify the accuracy of the software against expected output 4.It is performed before non-functional testing

Functional Testing types are
• Unit testing
• Smoke testing
• User Acceptance
• Integration Testing
• Regression testing
• Localization
• Globalization
• Interoperability

EXAMPLE:
Example of functional test case is to verify the login functionality
GPay

1. Adding a bank accounts
2. Sending and receiving money
3. Messaging
4. Allowing contacts

NON FUNCTIONAL TESTING:
Non functional testing is another type of software testing which is used to check the non functional aspects of a system like the performance the usability readability and so on it helps in testing the readiness of the system
How well the system performs is non-functionality testing. Non-functional testing refers to various aspects of the software such as performance, load, stress, scalability, security, compatibility etc., Main focus is to improve the user experience on how fast the system responds to a request.

1.How well the system performs is non-functionality testing
2.To ensure that the product stands up to customer expectations
3.To verify the behavior of the software at various load conditions
4.It is performed after functional testing

Non Functional Testing types
• Performance Testing
• Volume Testing
• Scalability
• Usability Testing
• Load Testing
• Stress Testing
• Compliance Testing
• Portability Testing
• Disaster Recover Testing
EXAMPLE:
google homepage open
non-functional test case is to check whether the homepage is loading in less than 2 seconds