Obayanju

let Organism = {
  canReproduce: true
};

Animal.prototype = Object.create(Organism);
Animal.prototype.walk = function () {
  console.log('Animals have the ability to walk');
};

Animal.prototype.canReproduce = false;

Obayanju

let Organism = {
  canReproduce: true
};

Animal.prototype = Object.create(Organism);
Animal.prototype.walk = function () {
  console.log('Animals have the ability to walk');
};
/** ------------ Animal.prototype *does not* mutate its parent, Organism ------------*/
console.log(Organism); // {canReproduce: true}

Obayanju

let Organism = {
  canReproduce: true
};

Animal.prototype = Organism;
Animal.prototype.walk = function () {
  console.log('Animals have the ability to walk');
};
/** ------------ Animal.prototype mutates its parent, Organism ------------*/
console.log(Organism); // { canReproduce: true, walk: [Function] }

Obayanju

let Organism = {
  canReproduce: true
};

Animal.prototype = Organism;
Animal.prototype.walk = function () {
  console.log('Animals have the ability to walk');
};

function Animal () {

Obayanju

let Organism = {
  canReproduce: true
};

Animal.prototype.walk = function () {
  console.log('Animals have the ability to walk');
};

function Animal () {
  this.legs = 4;

Obayanju

function Animal () {
//   'cat' would have a property 'legs' on itself when 'Animal' is called
  this.legs = 4;
}

// 'Animal.prototype' can be thought of as the parent
Animal.prototype.walk = function () {
  console.log('Animals have the ability to walk');
};

Obayanju

const bear = {
  claws: true,
  diet: 'carnivore'
};

function PolarBear() { 
  // ...
}

// PolarBear.prototype = bear;

Obayanju

var myArray = [ 1, 2, 3 ];
var it = myArray[Symbol.iterator]();

it.next(); // { value:1, done:false }
it.next(); // { value:2, done:false }
it.next(); // { value:3, done:false }
it.next(); // { done:true }

Obayanju

var myObject = {
	// define a getter for `a`
	get a() {
		return this._a_;
	},

	// define a setter for `a`
	set a(val) {
		this._a_ = val * 2;
	}

Obayanju

var myObject = {
	// define a getter for `a`
	get a() {
		return 2;
	}
};

Object.defineProperty(
	myObject,	// target
	"b",		// property name