Lesson 19 of 20

Modules & Browser Storage

Organize code and persist small browser values.

Introduction

Modules export reusable values and import them where needed. This keeps larger applications easier to navigate.

localStorage stores small string values in a browser. Do not use it for secrets or sensitive personal data.

Key insight

Example

localStorage.setItem("theme", "dark");
const theme = localStorage.getItem("theme");
console.log(theme);

This example shows the core modules & browser storage idea in a small, runnable program.

Real-world example

Test yourself

Ready to check your understanding?

Answer every question, then submit your quiz.

Try it yourself

Runs in your browser. Nothing is sent to a server.

Output appears here

Practice challenge

Store and read a preferred language from localStorage.