Hi Srinivas,
There is no similarity between event and Notification. Both are two different entities.
Event is anything that occurs and might cause something to occur (like triggering a notification).
on the other hand Notification is some kind of intimation that we trigger for user via email or sms.
So basically, only relationship between notification and event is:
Notifications are triggered on firing of events.
Event Fired ---------causes------> Notification Trigger.
