Prototype Enumerable map() Method

Syntax:

Iterator.map([context]);

Return Value :

Returns the results of applying the iterator to each element

Example:

<html>
<head>
<title>Prototype examples</title>
<script type="text/javascript" 
   src="/javascript/prototype.js">
</script>

<script>

function showResult(){
   alert( $R(1,5).collect(function(n) {return n * n;}) );
   // returns [1, 4, 9, 16, 25]
}

</script>
</head>

<body>

  <p>Click the button to see the result.</p>
  <br />
  <br />
  <input type="button" value="Result" onclick="showResult();"/>

</body>
</html>

To understand it in better way you can Try it yourself.