Object-oriented programming has been a hot topic in computer programming for quite a while now and JavaScript is no exception. But JavaScript does not support advanced OOP concepts such as inheritance or polymorphism. Instead, it tries to keep things as simple as possible by stripping things down to the bare minimum. Encapsulation is simply the process of wrapping up those functions and variables into different packages, called objects. The variables are known as properties of the object, and the function are then known as methods.

	Methods
	Properties
	Built-in Objects
	User-defined Objects

You can use methods to manipulate containers, which are objects. If you think of the browser as a stage, the actors and the sets are objects: the lines spoken and the actions taken are methods applied to the objects. You can create your method or function in JavaScript.

When methods are called, those methods usually act on some sort of data contained in the object. That data is called properties. A property is simply a variable that is contained inside an object.

Example :

Let us consider an automobile example. Let us create a object "myCar". In this you can have several methods. The two aspects of "myCar" state at any given time are
             Its speed
             Its direction
This data would be contained inside the object through its properties. Let's assume that the object contains the following two properties to model this state:
             Speed
             Direction
Now, you could modify the speed of the automobile represented by the object myCar directly by modifying this property. Properties are modified like any other variable, except that, much like methods, the property name must be prefixed by the name of the object you wish to modify the property of, separated by a period. Therefore, if you want to set the speed of myCar to 25, you would use the following statement;
             MyCar.Speed = 25;

For user convenience, the JavaScript provides some default objects. Some of the important objects are Math object, Date object, String object, document object etc. These objects include some methods to manipulate the data.

Example :

             var n = math.ceil(50.58);
             document.write(n);
In this example, we have used math object to find ceiling of the number 50.58, using the method called ceil().

Assume, you want to define an employee object that contains the employee's name, age, and salary. You would define this object as follows:

Function employee(name, age, salary)
{
             this.name = name;
             this.age = age;
             this.salary = salary;
}

It is important to note that you have not created a object, instead you have created a function that makes the objects. So, if you want to make an employee object with name siva, age 27, and salary $35,000, and assign it to the variable myEmployee, you would use the following code;

MyEmployee = new employee("siva", 27, 35000)