Requirements (Functional, non-functional and user requirements)

Question

can you please provide examples on requirements of the type (functional, non-functional and user requirements) of a website social network (lets say the facebook)?

thanx in advance

Answer 1

functional - correlate database records to deliver pertinent advertising
the actual what it's going to DO(the how of the use cases)

nonfunctional - able to load the page in under 3 seconds - "Sufficient network bandwidth may also be a non-functional requirement of a system"
there are a bunch of examples of this one on the wikipedia page: http://en.wikipedia.org/wiki/Non-functional_requirement

user - really just use cases - able to search for friends by email address
able to register an account
able to add friends
able to ...

moved some comments into the answer:
From Sara: can you add up another example , such as a registration process or a sign in process and thanx a lot your answer is useful but please provide more valuable examples (such this one ) if possible

almost any time you say "process" the ability to do the thing is use case, the how of that process is the functional req, the things the system has are mostly nonfunctional(system not software). does that make sense?

Specifically requested example
so the ability to log in is a user req

the actual steps in the login process are functional(form to receive credential, database query to verify validity, set auth token, etc)

and the fact that login should be fast is nonfunctional