What is an Executor? What is an Administrator?

I often receive calls from individuals whom were told by the bank that they need to be appointed as the Executor or Administrator of an Estate before any financial information on the decedent is released; and they want to know what that means.  What is an Executor?  What is an Administrator?  They have the same roles and functions essentially.  An Executor is actually named in a Last Will and Testament as the person to probate the estate.  If the person did not have a Last Will and Testament, then North Carolina has given that person the title of an Administrator.  The difference in titles is meant to differentiate whether the person had a Last Will and Testament or not.