Modules & Code Organization

Every project so far in this course has lived in one file. Real projects don’t. This module covers ES modules, JavaScript’s built-in system for splitting code across files and sharing it between them.

Why This Matters

A single giant file becomes unmanageable fast, and it makes reusing code across projects nearly impossible. Modules solve both problems: each file has a clear job, and any file can use code from any other.

What You’ll Learn

• ES modules, and how they differ from just loading multiple <script> tags
• import and export, for sharing code between files
• Dynamic imports, for loading a module only when you need it
• Organizing a small project across multiple files
• What a bundler does, and why real projects use one

Outcome

By the end of this module, you’ll be able to organize a project into focused, reusable files instead of one long script.

Let’s get started.