What is "contextmenu"?

What is "contextmenu"?

I saw an example on jquery-practical-exercise
The entire code 
  1. <!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
    <script src="Scripts/jquery-2.1.0.min.js"></script>
</head>
<body>
    <script type="text/javascript">
        $(document).ready(function () {
            $(document).bind("contextmenu", function (e) {
                return false;
            });
        
    </script>
</body>
</html>

My question is what is "contextmenu" here? By the bind

Inside the parentheses， There are three of them

  • eventType
    Type:   String
    A string containing one or more DOM event types, such as "click" or "submit," or custom event names.
  • eventData
    Type:   Anything
    An object containing data that will be passed to the event handler.
  • handler
    Type:   Function(   Event  eventObject )
    A function to execute each time the event is triggered.
 
So what is "contextmenu"? Is it eventType or eventData or something else?