1 - Getting started

Chapter 1: Getting Started with JavaScript

What is JavaScript?

JavaScript: A high-level programming language for adding interactivity to web pages.
Core Technologies: Part of the web trio—HTML, CSS, and JavaScript.
Use Cases:
- Adding behaviors to websites (e.g., form validation).
- Creating animations.
- Updating data without refreshing the page.
- Used in browsers, servers, and mobile apps.

Setting Up the Development Environment

Tools You Need

Text Editor/IDE: Choose any of the following:
- Visual Studio Code: Popular, full of extensions for JS development.
- Sublime Text: Fast and simple.
- Atom: Open-source, lots of plugins.
Web Browser: Modern browsers like Google Chrome, Firefox, or Edge have built-in developer tools:
- Developer Tools: Access via F12 or right-click → "Inspect". Useful for debugging JS.
Node.js: To run JavaScript outside the browser.
- Download: From nodejs.org.
- Check Installation: Run node -v in terminal to verify.
Git for Version Control:
- Git: Install from git-scm.com.
- GitHub: Use to host and share your projects.

Writing Your First JavaScript Program

Create a New HTML File

Name it index.html.
Write this code:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>First JavaScript Program</title>
</head>
<body>
    <h1>Hello, JavaScript!</h1>
    <script>
        console.log("Hello, World!");
    </script>
</body>
</html>

Explanation
- HTML Structure: Basic page setup.
- JavaScript: Embedded using <script> tag.
- Console Output: console.log() prints to the browser's console (open with F12).

Understanding JavaScript in Browsers and Node.js

Environments Where JavaScript Runs

Browsers
- JavaScript runs in all modern browsers.
- Developer Tools:
  - Press F12 to open.
  - Use for debugging, inspecting elements, and testing JS code.
Node.js
- Server-Side JavaScript: Allows JS to run on the server.
- Built-In Modules: For handling files, HTTP, etc.
- Check Installation: Run:
  node -v
  - If it displays a version, Node.js is installed.

Summary

JavaScript is crucial for interactive web content.
Set up with Text Editor, Web Browser, Node.js, and Git.
You wrote your first JavaScript using console.log().
JavaScript runs in both Browser and Node.js environments.

Next Chapter: JavaScript Basics

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Last updated 1 year ago