[otrs] Notification, Notification(Event), Vs Autoreponse

Hi All, I have been using Autoresponse<>queue to automatically respond to customers when new tickets are created. My question is, how can I automatically notify customers when their tickets are closed/updated? I have gone through "Notification" and "Notification(Event)" - Which of these can be used as an automatically triggered response to an event and how? (I'm using otrs2.4.4) Michael