Event is a step that leads to the action or status change in the project management. It has no time and is the start or the end of the activity. The event is represented by a node in the network. A network that consists of the descrete-event nodes, the activities without definite duration but a completion date (milestone), is an event-on-node network (ENN). Events and their dependencies contain therefore th activity-on-arrow network (AoA) and the activity-on-node network (AoN). The project management checks the event effects on the project to obviate or minimize the project risks such as unforeseeable and occurred events.
There are two tapes of the events the actor-initiating events and system events in the project management. The system events are not always impacted by the actors. They represent marketing development and law changes.