JavaScript

Bring pages to life.

The language of the web — variables, functions, the DOM, events, and asynchronous programming with the event loop.

Start course0 of 12 lessons complete

Chapter 1

JavaScript Foundations

0/3

What is JavaScript?

Discover how JavaScript transforms static web pages into living, interactive experiences — and write your first lines of code.

02Beginner

Variables & Data Types

Learn how to store and label information in JavaScript using let and const, and meet the five primitive types your programs will use every day.

03Beginner

Operators & Expressions

Learn how JavaScript does math, compares values, combines logic, and builds strings — the everyday building blocks every program depends on.

Chapter 2

Data & Logic

0/5

04Beginner

Arrays

Learn how to store and work with ordered lists of data using JavaScript arrays, from basic indexing to the powerful map, filter, and reduce methods.

05Beginner

Objects

Learn how to group related data and behavior together using JavaScript objects — the backbone of almost every real-world JS program.

06Beginner

Conditionals

Teach your programs to make decisions using if/else, comparison and logical operators, the ternary shortcut, switch statements, and JavaScript's quirky truthy/falsy rules.

07Beginner

Loops

Learn how to repeat work automatically with JavaScript's for, while, for...of, and for...in loops — and when to reach for each one.

08Beginner

Functions

Learn how to package reusable logic into functions, pass data in with parameters, get results back with return, and write the sleek arrow-function syntax.

Chapter 3

The DOM & Events

0/2

09Intermediate

The DOM

Learn how the browser turns your HTML into a live tree of objects that JavaScript can read, update, and style on the fly.

10Intermediate

Events & Listeners

Learn how to make your web pages respond to user actions by wiring up event listeners, working with the event object, and understanding how events travel through the DOM.

Chapter 4

Asynchronous JavaScript

0/2

11Intermediate

Promises & async/await

Learn why JavaScript needs async code, how Promises track work in progress, and how async/await makes the whole thing read like a story.

12Advanced

The Event Loop

Peek under the hood of JavaScript to see exactly how the call stack, Web APIs, and two separate queues work together to make async code possible.