(function (){
    alert(this);
    var doors = 4;
    var engine = 'v8';
    var carType = 'hatchback';
    var that = this;
    this.Car = {};
    Car.getDoors = function(){
        return doors;
    }
})();

//onload
window.onload = function(){
	alert(Car.getDoors());
	alert(window.doors);
}