object methods in js

Object Methods
As mentioned in Chapter 1, you can add and remove properties from
objects at any time. When a property value is actually a function, the
property is considered a method. You can add a method to an object in
the same way that you would add a property. For example, in the following code, the person variable is assigned an object literal with a name property and a method called sayName.

var person = {
 name: "Nicholas",
 sayName: function() {
 console.log(person.name);
 }
};

person.sayName(); // outputs "Nicholas"
Note that the syntax for a data property and a method is exactly
the same—an identifier followed by a colon and the value. In the case
of sayName, the value just happens to be a function. You can then call
the method directly from the object as in person.sayName("Nicholas").