This EventTarget is specified in the Event's target attribute. When the event reaches the target, any event listeners registered on the EventTarget are triggered. All EventListeners on the EventTarget will be triggered by any event which is received by that EventTarget, but there is no guarantee as to order. There are two types of event flow - bubbling and capturing. Event capture is the process by which an EventListener registered on an ancestor of the event's target can intercept events of a given type before they are received by the event's target.
Capture operates from the top of the tree down, mostly starting at the document object itself.
Bubbling works in the opposite direction - after the event is dispatched to its target EventTarget and any event listeners found there are triggered, bubbling events will then trigger any additional event listeners found by following the EventTarget's parent chain upward, checking for any event listeners registered on each successive EventTarget. This upward propagation will continue up to and including the Document. With the combination of both of these flows, an event can be triggered anywhere in the document. The stopPropagation method can be used to stop the event flow. The events themselves have context to be used when carrying out the action specified once the event happens.