Difference between an RN and a NP?

[Mnstn, BSN, RN]

I know there is a difference but I am foggy on what a Nurse Practitioner can do that a RN can't. Do NP's work for doctors or how does the whole authority thing I guess you could say work in a hospital? What is the NP's role in the hospital? I'm sorry if my question is confusing, I am trying to word it correctly.

[yellow finch, BSN, RN]

This might help.

http://en.wikipedia.org/wiki/Nurse_practitioner

[Mnstn, BSN, RN]

Ok thanks, Wikipedia can be such a good source sometimes.