Whenever an event occurs, an
event object is generated. The nature of this object depends on the event which generated it. To access the
event object, simply pass the keyword
event to whichever function is handling the event:
<a href = "#" onClick = "handleClick(event); return false; ">Click me!</a>.
event object is most frequently accessed when you want to know which key a user has pressed, or precisely where the mouse is.