Get Started with Node.js

In this module, we will dive into the world of Node.js and get you started on your journey to becoming a proficient Node.js developer. We'll cover the basics, set up your development environment, and write your first Node.js application.

Table of Contents

• Table of Contents
• What is Node.js?
  • Why Use Node.js?
• Setting Up Node.js
  • Installation
  • Verifying Installation
• Your First Node.js Application

What is Node.js?

Node.js is a runtime environment that allows you to run JavaScript on the server-side. It's built on the V8 JavaScript engine and is designed for building scalable network applications. Node.js is especially popular for building web servers and APIs.

Why Use Node.js?

• JavaScript everywhere: Node.js allows you to use the same language (JavaScript) on both the client and server sides of web development.
• Fast and efficient: It's built on the V8 JavaScript engine, making it one of the fastest runtime environments.
• Non-blocking I/O: Node.js uses an event-driven, non-blocking I/O model, making it ideal for handling asynchronous tasks.

Setting Up Node.js

Before you start coding in Node.js, you'll need to set up your development environment.

Installation

1. Visit the Node.js official website.
2. Download the LTS (Long-Term Support) version for stability.
3. Follow the installation instructions for your operating system.

Verifying Installation

To make sure Node.js is installed correctly, open your terminal (or command prompt) and run the following commands:

node -v

OR

npm -v

You should see the installed Node.js and npm versions.

Your First Node.js Application

Now that you have Node.js installed, let's create your first Node.js application. We'll start with a simple "Hello, Node.js!" example.

1. Create a new folder for your project and navigate to it in the terminal.

   mkdir my-node-app

   cd my-node-app

2. Create a file named app.js using a code editor of your choice (e.g., Visual Studio Code).

3. In app.js, add the following code:

   app.js

   // Import the built-in 'http' module
   const http = require('http');
   
   // Create an HTTP server
   const server = http.createServer((req, res) => {
     res.writeHead(200, { 'Content-Type': 'text/html' });
     res.end('Hello, Node.js!\n');
   });
   
   // Listen on port 3000
   server.listen(3000, 'localhost', () => {
     console.log('Server is running at http://localhost:3000/');
   });

This code does the following:

• Imports the built-in 'http' module.
• Creates an HTTP server that listens on port 3000.
• Responds with "Hello, Node.js!" to any incoming requests.

4. Save the file and return to the terminal. Run your Node.js application:

   node app.js

5. Open your web browser and visit http://localhost:3000/. You should see "Hello, Node.js!" displayed in your browser.

http://localhost:3000

Hello, Node.js!

Congratulations! You've just created your first Node.js application.