An Event is an automatic notice of a specific occurrence or change in the application. There are five types of events:

• Business Events
• Integration Events
• Global Events
• Database Trigger Events
• Page Trigger Events

If we want to make changes to the existing flow of business logic for our Extension, we must use the events that are made available by Microsoft. You can find more information on using events at https://msdn.microsoft.com/en-us/library/mt299398(v=nav.90).aspx and by watching the video at https://www.youtube.com/watch?v=zQHVv7PV8u8&t=2843s.