JavaScript events

✒ Reference: This stackoverflow question

What is an event object?

event is a JavaScript object that contains information about the action trigerred by the user. (events like click, keydown, etc.)

How do you handle an event object?

To handle events, you bind an event handler to a component that you are interested in. An event handler is a function which is executed when the event happens. The way to bind the handler to the element is by doing element.addEventListener(eventName, handler). eventName is a string, and it is the name of the event that you are interested in. (i.e. click)

event as a parameter

The event object is passed into the handler function by default. When it is defined, it is usually passed in as e.