function call in javascript

I was studying russkey.mozdev.org source code to learn how to write Firefox extension.

Found this style of function call in javascript.

var collection =   {

 hello : function() {
  document.write("Hello World!");
 },
 
 understand : function() {
  document.write("<br/>Understand!");
 },
 
 bye : function() {
  document.write("<br/>bye!");
 }
 
};


var m = new collection.hello();
var n = new collection.understand();
var o = new collection.bye();

The output will

Hello World!
Understand!
bye!