Prototypal Inheritance: https://medium.freecodecamp.com/understanding-prototypal-inheritance-in-javascript-with-css-93b2fcda75e4#.d0a4x364q

prototypal-inheritance-demo.js

var Circle = {
	radius : 0,
	create : function(radius) {
		// Creating prototypal linkage using Object.create
		var obj = Object.create(this);
		obj.radius = radius;

		return obj;
	},
	area : function() {
		return Math.PI * this.radius * this.radius;
	}
};
var circle5 = Circle.create(5);
var circle10 = Circle.create(10);