Simple Events

A simple event definition is a set of properties related to a given activity, while a simple event is an instance of a simple event definition.

Simple Event Definition
The simple event definition includes information for evaluation by rules, meta-data that provides context, and a separate payload — a set of data relevant to the activity. For example, suppose you are interested in monitoring the creation of new employee records. You might create a simple event definition that includes important fields from the employee record, perhaps the social security number, department, and salary. You could then write a rule to create an instance of this simple event each time a new employee record is created.
Simple Event
The simple event is an instance of a simple event definition and a record of a single activity that occurred at a single point in time.

Just as you cannot change the fact that a given activity occurred, once an event is asserted into the Rete network, you can no longer change it. (Before assertion you can use an event preprocessor to enrich the event, however.) Simple events expire when their time to live has elapsed, unless TIBCO BusinessEvents has instructions to consume them prior to that time.