Gain insights into writing cleaner, modular, scalable JavaScript code through OOP. Explore basics to advanced concepts like prototypal inheritance, method overriding, and ES6 features.

Learn to write cleaner, more modular, and more scalable code in JavaScript by gaining mastery of Object Oriented Programming (OOP). 

You'll start with the basics of object-oriented programming and build up to more advanced concepts such as prototypal inheritance, prototype chaining, method overriding and mixins. Along the way, you'll learn how each concept applies to JavaScript's sometimes unique way of handling things. You'll also see how various JavaScript features make it particularly convenient for OOP, with particular emphasis on changes introduced in ES6.

This course is filled with hands-on coding challenges, playgrounds, snippets, and illustrations to keep things interactive.

Learn Object-Oriented Programming in JavaScript

# Hiding Data

Till now, all the constructor function properties were easily accessible outside of it, and their values could be modified without any restrictions. In both ES5 and ES6 versions of JavaScript, there is no formal support for access modifiers using *keywords* such as `public`, `private` or `protected`. By default, all properties are public; hence, they can easily be accessed. 

Let's discuss property protection for the ES5 version.

Before we get into details, let's take a look at the following term:

> **internal property**: a *property* or *method* that can only be accessed by methods present *inside* the *constructor* function.

An *internal property* can then be considered protected from being accessed in an unauthorized manner.

# Example

Let's start by taking a look at how properties were being defined inside the constructor function previously: 

This lesson explains the steps to protect properties and teaches us how to access these protected properties.

Introduction

Objects in JavaScript

Functions as Objects

OOP in JS - Exam 1

Classes

Inheritance

OOP in JS - Exam 2

Data Encapsulation in ES5

Hiding Data