[otrs] Clarification required about Internal Note, External Note and Note Report

Hi, 1. While closing a call there is an option for selecting Internal Note, External Note and Report. I am not able understand exactly how to make use of this functionality. I request some to tell me about the difference between each one of them. 2. After closing a ticket, is it possible to send the contents recorded in "text area" of closing ticket menu to requester, agent and queue owner. Regards, Prafulla Kumar