Object.Prototype sample code from MDN - https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/prototype

Object.Prototype.js

var Person = function() {
  this.canTalk = true;
};

Person.prototype.greet = function() {
  if (this.canTalk) {
    console.log('Hi, I am ' + this.name);
  }
};

var Employee = function(name, title) {
  Person.call(this);
  this.name = name;
  this.title = title;
};

Employee.prototype = Object.create(Person.prototype);
Employee.prototype.constructor = Employee;

Employee.prototype.greet = function() {
  if (this.canTalk) {
    console.log('Hi, I am ' + this.name + ', the ' + this.title);
  }
};

var Customer = function(name) {
  Person.call(this);
  this.name = name;
};

Customer.prototype = Object.create(Person.prototype);
Customer.prototype.constructor = Customer;

var Mime = function(name) {
  Person.call(this);
  this.name = name;
  this.canTalk = false;
};

Mime.prototype = Object.create(Person.prototype);
Mime.prototype.constructor = Mime;

var bob = new Employee('Bob', 'Builder');
var joe = new Customer('Joe');
var rg = new Employee('Red Green', 'Handyman');
var mike = new Customer('Mike');
var mime = new Mime('Mime');

bob.greet();
// Hi, I am Bob, the Builder

joe.greet();
// Hi, I am Joe

rg.greet();
// Hi, I am Red Green, the Handyman

mike.greet();
// Hi, I am Mike

mime.greet();

OOP.JavaScript.Methods.js

var Person = function (firstName) {
  this.firstName = firstName;
};

Person.prototype.sayHello = function() {
  console.log("Hello, I'm " + this.firstName);
};

var person1 = new Person("Alice");
var person2 = new Person("Bob");
var helloFunction = person1.sayHello;

// logs "Hello, I'm Alice"
person1.sayHello();

// logs "Hello, I'm Bob"
person2.sayHello();

// logs "Hello, I'm undefined" (or fails
// with a TypeError in strict mode)
helloFunction();                                    

// logs true
console.log(helloFunction === person1.sayHello);

// logs true
console.log(helloFunction === Person.prototype.sayHello);

// logs "Hello, I'm Alice"
helloFunction.call(person1);