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The JavaScript Interview Handbook: 100+ Interview Questions

The ultimate guide to JavaScript interviews. Developed by FAANG engineers, practice with real-world interview questions, gain confidence, and get interview-ready in just a few hours.

Intermediate

151 Lessons

10h

Certificate of Completion

The ultimate guide to JavaScript interviews. Developed by FAANG engineers, practice with real-world interview questions, gain confidence, and get interview-ready in just a few hours.

AI-POWERED

Mock Interview

Explanations

AI-POWERED

Mock Interview

Explanations

This course includes

198 Playgrounds

36 Challenges

61 Quizzes

Course Overview

Course Content

Recommendations

Course Overview

Preparing for coding interviews can be a long, arduous process. Many developers will tell you they spend countless hours grinding through hundreds of coding questions in order to feel confident. This course will help simplify the grind by showing you what topics to spend your time on and what questions you can expect within those topic areas. In this course you will focus on the fundamental concepts of JavaScript that interviewers expect you to know. You’ll practice interview questions related to: JS langu...Show More

Preparing for coding interviews can be a long, arduous process. Many developers will tell you they spend countless hours grindin...Show More

Course Content

Introduction

2 Lessons

Get familiar with essential JavaScript concepts to ace frontend interviews.

About This Course

Evaluate Yourself

Language Basics

38 Lessons

Discover the logic behind JavaScript basics, including hoisting, closures, scope, and array manipulation.

Quiz: Hoisting

Solution Review: Hoisting

Challenge: Create an Amount

Solution Review: Create an Amount

Challenge: Check Parentheses

Solution Review: Check Parentheses

Quiz 1: Arrow Functions

Solution Review: Arrow Functions

Quiz 2: Arrow Functions

Solution Review: Arrow Functions

Challenge: Where to Insert

Solution Review: Where to Insert

Quiz: Call, Apply, Bind

Solution Review: Call, Apply, Bind

Quiz 1: Closure

Solution Review: Closure

JavaScript Execution: Call Stack & Event Loop

Immediately Invoked Function Expressions (IIFE)

Quiz: Closure, `setTimeout`, Scopes

Solution Review: Closure, `setTimeout`, Scopes

Quiz: Closure, `setTimeout`, IIFE

Solution Review: Closure, `setTimeout`, IIFE

Challenge: Create Phone Number

Solution Review: Create Phone Number

Challenge: Insert Elements

Solution Review: Insert Elements

Challenge: Bind Function

Solution Review: Bind Function

Quiz: Rest & Spread Syntax

Solution Review: Rest & Spread Syntax

Challenge: Destructuring

Solution Review: Destructuring

Challenge: Array Destructuring

Solution Review: Array Destructuring

Challenge: Return the Cat

Solution Review: Return the Cat

Challenge: Destructure Undefined

Solution Review: Destructure Undefined

Type coercion

20 Lessons

Break apart type coercion concepts using "typeof", "instanceof", prototypes, validation, and inheritance in JavaScript.

Quiz 1: "typeof" Operator

Solution Review: "typeof" Operator

Challenge: Validate Arguments

Solution Review: Validate Arguments

Quiz 1: "instanceof" Operator

Solution Review: "instanceof" Operator

Challenge: Inheritance Check

Solution Review: Inheritance Check

Quiz 2: "instanceof" Operator

Solution Review: "instanceof" Operator

Challenge: Instance of Array?

Solution Review: Instance of Array?

Challenge: Check Instance of Variables

Solution Review: Check Instance of Variables

Quiz: prototype.toString & "typeof"

Solution Review: prototype.toString & "typeof"

Challenge: Array or Not?

Solution Review: Array or Not?

Challenge: Validate the Date

Solution Review: Validate the Date

Event Handling

8 Lessons

Break down complex ideas in JavaScript event handling concepts and their interview applications.

Quiz: Call Stack & Event Loop

Solution Review: Call Stack & Event Loop

Quiz: Event Bubbling

Solution Review: Event Bubbling

Quiz: Event Capturing

Solution Review: Event Capturing

Quiz: Event Delegation

Solution Review: Event Delegation

Asynchronous Callbacks

16 Lessons

Map out the steps for understanding and solving asynchronous programming challenges with callbacks, promises, and async/await.

Challenge: Callback Functions

Solution Review: Callback Functions

Challenge: Check the Names

Solution Review: Check the Names

Challenge: Asynchronous Callback Functions

Solution Review: Asynchronous Callback Functions

Quiz 1: Promises

Solution Review: Promises

Challenge: Even or Odd?

Solution Review: Even or Odd?

Quiz 2: Promises

Solution Review: Promises

Challenge: Print Numbers Sequentially

Solution Review: Print Numbers Sequentially

Quiz: Async & Await

Solution Review: Async & Await

OOP in JavaScript

22 Lessons

Focus on understanding OOP in JavaScript through quizzes, challenges, and solution reviews.

Quiz: Native & Host Objects

Solution Review: Native & Host Objects

Quiz: `this` Keyword

Solution Review: `this` Keyword

Challenge: Prototype Property

Solution Review: Prototype Property

Challenge: isPrototypeOf

Solution Review: isPrototypeOf

Challenge: ES6 Classes

Solution Review: ES6 Classes

Quiz: Inheritance

Solution Review: Inheritance

Challenge: Prototypal Inheritance

Solution Review: Prototypal Inheritance

Challenge: ES6 Inheritance

Solution Review: ES6 Inheritance

Quiz: "super" Keyword

Solution Review: "super" Keyword

Challenge: Counting Animals

Solution Review: Counting Animals

Challenge: Let's Make a Burger

Solution Review: Let's Make a Burger

Functional Programming

25 Lessons

Master functional programming concepts through practical quizzes, challenges, and in-depth solution reviews.

Quiz: Pure Function

Solution Review: Pure Function

Challenge: Purify the Function

Solution Review: Purify the Function

Challenge: Let's Add Properties

Solution Review: Let's Add Properties

Quiz: Shallow Copy

Solution Review: Shallow Copy

Challenge: Shallow to Deep

Solution Review: Shallow to Deep

Quiz: Higher Order Functions

Solution Review: Higher Order Functions

Challenge: Make Maximum Donuts

Solution Review: Make Maximum Donuts

Challenge: Calculate Score

Solution Review: Calculate Score

What Are Currying Functions?

Challenge: Let's Curry!

Solution Review: Let's Curry!

Quiz: Partial Functions

Solution Review: Partial Functions

Challenge: Make a Sentence

Solution Review: Make a Sentence

Challenge: Club Entry System

Solution Review: Club Entry System

Security

6 Lessons

Step through key JavaScript security concepts such as same-origin policy, strict mode, and object manipulation protections.

Quiz: Same Origin Policy

Solution Review: Same Origin Policy

Quiz: "strict" Mode

Solution Review: "strict" Mode

Challenge: Catch the Error

Solution Review: Catch the Error

DOM and Web Browser

14 Lessons

Walk through various DOM manipulation techniques and problem-solving challenges with hands-on JavaScript tasks.

Challenge: Hide & Show

Solution Review: Hide & Show

Challenge: Get Elements Using Attributes

Solution Review: Get Elements Using Attributes

Challenge: Add a Class

Solution Review: Add a Class

Challenge: Destroy the Button

Solution Review: Destroy the Button

Challenge: Is a Child?

Solution Review: Is a Child?

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