In ABAP Objects, events are declared as components of classes. SAP makes a distinction between instance events and static events. Triggers and handlers can be objects and classes, depending on whether they are instance events, static events, or event handler methods.
Instance events are declared using the EVENTSstatement. They can only be triggered in instance methods.
Static events are declared using the CLASS-EVENTS statement. All methods (instance or static) can trigger them, but only static events can be triggered by static methods.