What is the difference between Functional and Non Functional testing?Give Some Examples?

Functional Testing:

Is is a process to validate each functionality of a software /product is implemented as user expectation.

Types of Functional Testing: Unit/Smoke/Integration/Regression/system/User acceptance Testing.

Example: Facebook -- Test whether able to login Facebook page by providing User name and Password.

Non-Functional Testing:

To Ensure Software /Product meets the specific performance of requirements and to test the non functional aspects of application performance/reliability/security .

Types of Non Functional Testing:
Load/Stress/Scalability/Security testing.

Example: Time required to load the Facebook page based.