MODULE 6 · 13 lessons · 13 challenges

JavaScript in the Browser

JavaScript becomes useful when it can read and change the page. This module is the bridge from "the language" to "the running web page" — selecting elements with querySelector, mutating HTML and CSS from JS, listening to clicks and keystrokes, and building two small interactive apps (a UI calculator and a TODO list) that pull it all together.

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All lessons in this module

JavaScript in the Browser

All lessons in this module

1. JavaScript in the Browser — Introduction

2. Selecting Elements

3. Manipulating HTML

4. Manipulating CSS

5. Built-in DOM Events

6. Project — UI Calculator

7. Project — TODO List

8. Dynamic Elements

9. Custom Data Attributes

1. IntersectionObserver — Lazy Load & Infinite Scroll

2. ResizeObserver — Components That Adapt to Their Box

3. MutationObserver — Reacting to DOM Changes

4. Drag-and-Drop API + File API