Event & Event Handling

The EventTarget interface is implemented by objects that can react to certain events [MDN, samthor.au].

A script can create an event using the Event constructor. Such an event is called synthetic event (unlike native events that are dispatched by the browser). To actually fire the event, dispatchEvent is used. [MDN]

A CustomEvent is similar to an Event with the difference that it may have a detail property on the event options. That can be used to pass additional information regarding the event to a listener. [MDN]

Handlers for native events are executed asynchronously. Custom events that are fired with dispatchEvent are executed synchronously. [MDN]