Node.js Tutorial: A Comprehensive Guide for Beginners
Node.js has revolutionized the way developers build scalable and efficient applications. Whether you’re new to programming or looking to expand your skill set, this tutorial will guide you through the essentials of Node.js.

What is Node.js?
Node.js is an open-source, cross-platform JavaScript runtime environment that executes JavaScript code outside of a web browser. Built on Chrome’s V8 JavaScript engine, it allows developers to use JavaScript for server-side scripting, enabling the creation of dynamic web page content before the page is sent to the user’s browser.
Why Use Node.js?
Asynchronous and Event-Driven: Node.js uses a non-blocking I/O model, making it efficient and suitable for real-time applications.
Single Programming Language: With Node.js, you can use JavaScript for both client-side and server-side development, streamlining the development process.
Vast Ecosystem: The Node Package Manager (NPM) provides access to thousands of libraries and modules, accelerating development.
Setting Up the Node.js Environment
Download and Install Node.js:
Visit the official Node.js website and download the installer suitable for your operating system.
Run the installer and follow the on-screen instructions to complete the installation.
Verify the Installation:
Open your terminal or command prompt.
Type
node -v
to check the Node.js version andnpm -v
to check the NPM version.If both commands return version numbers, the installation was successful.
Your First Node.js Application
Let’s create a simple “Hello, World!” application to get started:
Create a New File:
- Create a file named
app.js
in your project directory.
- Create a file named
Write the Code:

3. Run the Application:
In the terminal, navigate to your project directory.
Execute the command
node app.js
.Open your browser and navigate to
http://127.0.0.1:3000/
to see the message “Hello, World!”.
Understanding Modules in Node.js
Modules are reusable blocks of code that help keep your code organized. Node.js has a set of built-in modules, such as http
, fs
, path
, and more. You can also create your own modules or install third-party modules using NPM.
Working with the File System
Node.js provides the fs
module to interact with the file system. Here’s an example of reading a file asynchronously:

This code reads the content of example.txt
and logs it to the console.
Using NPM (Node Package Manager)
NPM is a package manager for Node.js packages or modules. It allows you to install and manage dependencies for your projects.
Initialize a Project:
- Run
npm init
in your project directory and follow the prompts to create apackage.json
file.
- Run
Install a Package:
- Use
npm install package-name
to install a package and add it to your project dependencies.
- Use
Building a Simple Web Server with Express.js
Express.js is a minimal and flexible web application framework for Node.js. It simplifies the process of setting up a web server.
Install Express.js:
- Run
npm install express
in your project directory.
- Run
Create a New File:
- Create a file named
server.js
.
- Create a file named
Write the Code:

4. Run the Server:
Execute
node server.js
in the terminal.