modules.html

<html>

<head>

<script>

var Exposer = (function() {
  var privateVariable = 10;
  var publicVariable = 20;

  var privateMethod = function() {
    console.log('Inside a private method!');
    privateVariable++;
  }

  var methodToExpose = function() {
    console.log('This is a method I want to expose!');
  }

  var otherMethodIWantToExpose = function() {
    privateMethod();
  }
  
  var methodWithParamters = function (a,b) {
	console.log(a + ' ' + b);
  }

  return {
      first: methodToExpose,
      second: otherMethodIWantToExpose,
	  third: methodWithParamters,
	  publicVariable
  };
})();

Exposer.first();        // Output: This is a method I want to expose!
Exposer.second();       // Output: Inside a private method!
Exposer.methodToExpose; // undefined
Exposer.third("Hello", "World"); // Method accepting paramters
console.log(Exposer.publicVariable); // Printing public variable

</script>
</head>

<body>
</body>
</html>