There are four ways in which keys and values can be assigned to an object: (1,2 are ECMAScript 3 compatible approaches and 3,4 are ECMAScript 5 only compatible approaches)

ObjectTest.js

//1 way
//setter
newObject.someKey = "some value";
//getter
var key = newObject.someKey;

//2nd way
// Set properties
newObject["someKey"] = "some value";
// Get properties
var key = newObject["someKey"];


//3rd way
Object.defineProperty( newObject, "someKey", {
    value: "some value",
    writable: true,
    enumerable: true,
    configurable: true
});

//simple way
var defineProp = function ( obj, key, value ){
  config.value = value;
  Object.defineProperty( obj, key, config );
};

// To use, we then create a new empty "car" object
var myCar= Object.create( null );

// Populate the object with properties
defineProp( myCar, "brand",  "Toyota" );
defineProp( myCar, "year", "2009" );
defineProp( myCar, "bandnew", true );

//4th way 
Object.defineProperties( newObject, {

  "firstKey": { 
    value: "some vlaue", 
    writable: true 
  },
 
  "secondrKey": { 
    value: "second value",
    writable: false 
  } 
 
});

//3 and 4 can be used any 1,2 getter mthod to get values