I am new to networking and all this DNS thing. 

I have the following questions

* What is an Authoritative Nameserver ?
* What is a Recursive Resolver ?

Please help/ guide me out on this. 

I have read [Authoritative Nameserver](http://en.wikipedia.org/wiki/Name_server#Authoritative_name_server), but I was not able to clearly understand it. Can one please explain me in some simple terms.