An event is a signal to an object that something has happened, will happen, or is just about to happen. An event is usually an action taken by a player character or creature, but not always. When an event occurs, the module responds by running a script that has been associated with the event in question. Each object that might be affected by the event will receive this notification. Objects that receive the event can respond to that notification if they wish; how a particular object responds to an event is detailed within a script. A script tells the object what to do when an event occurs.