The following is taken directly from the w3 specifications:
"The Event interface is used to provide contextual information about an event to the handler processing the event. An object that implements the Event interface is generally passed as the first parameter to an event handler. More specific context information is passed to event handlers by deriving additional interfaces from Event which contain information directly relating to the type of event they accompany. These derived interfaces are also implemented by the object passed to the event listener."
In other words, an event is a user input action that takes place in the browser. If your user clicks, touches, drags, or rotates, an event will fire. If you have event listeners registered to those particular events, the listeners will catch the event and determine the event type. The listeners...
