property: The value representing the state of the object.
method: Operation to refer to and manipulate the property.
object literal
This is a notation to create the value using understandable character or promised 기호. The original way is to use object literal for creating object in JavaScript.
Object literal defines property more than 0 within ({}).
The key of property has a role of indentifying as a name that can access to its value.
Method can be used as value of property because function in JavaScript is a object.
