Event in the Application System 
You use events in the application system to define whether changes to application objects or processes are relevant to supply chain event management (SCEM-relevant).
The application system sends the SCEM-relevant data for these events to SAP Event Management (SAP EM).
The application system can create multiple events at the same time for a change to an application object. SAP EM can also process multiple events in the event handlers.
Example
You use two different events for a delivery process to report the following for an event handler:
The completeness of a delivery
A change to the delivery date of a delivery item