Lesson 31 of 3394%

(Progress persistence is disabled until Phase 9)

JavaScript
Intermediate
20 min

Local Browser APIs

Use built-in browser tools.

Learning Objectives

  • localStorage

Local Browser APIs

Welcome to this lesson on Local Browser APIs. JavaScript is the programming language of the web, and local browser apis is a fundamental piece of that ecosystem.

Explanation

When your browser loads a web page, the HTML creates the structure, the CSS creates the style, and JavaScript creates the interactivity. JavaScript can update both HTML and CSS in real-time.

Code Examples

Here is a simple snippet demonstrating this concept:

const theme = localStorage.getItem("theme");\n```

### Explanation of Code

In the example above, we define the logic required to implement the concept, and then execute it. The JavaScript engine parses this syntax and runs it.

<Callout type="warning">
**Common Mistake:** Watch out for syntax errors! Missing a bracket or a semicolon can sometimes break your entire script.
</Callout>

### Try It Yourself

Put this into practice! The BrowserCode runtime allows you to execute JavaScript securely in your browser.

<TryItButton />

### Key Takeaways
- JavaScript makes pages interactive.
- Always check your browser console for errors.

Lesson Progress

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