Node.js and Express.js Essentials — A Quickstart Guide for Beginners

3 min readMar 24, 2023

Introduction

Node.js has become a popular choice for developers when building scalable and efficient web applications. Express.js is a powerful web framework for Node.js that simplifies server-side development. In this article, we’ll walk through the basics of getting started with Node.js and Express.js, including setting up a development environment, creating a simple web server, and building a basic web application.

Prerequisites

Before diving into Node.js and Express.js, ensure you have the following prerequisites:

A basic understanding of JavaScript and Node.js.
Node.js installed on your system. Download the latest version from the Official Website.
A code editor of your choice, such as Visual Studio Code, Sublime Text, or Atom.

Setting up Your Development Environment

To start using Node.js and Express.js, you need to create a new project directory and initialize a Node.js application:

Create a new directory for your project and navigate to it using the terminal or command prompt.
Run the command npm init to initialize a new Node.js application. Follow the prompts to set up your package.json file.
Install Express.js by running the following command: npm install express --save. This will add Express.js as a dependency in your package.json file.

Creating a Simple Web Server with Express.js

Now that your development environment is set up, let’s create a simple web server using Express.js:

Create a new file called app.js in your project directory.
Open app.js and import the Express module:

const express = require('express');

Create a new Express application:

const app = express();

Define a route for the root URL (/) that returns a "Hello, World!" message:

app.get('/', (req, res) => {
  res.send('Hello, World!');
});

Set your application to listen on a specific port:

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

Now, start your application by running the command node app.js in your terminal. Your server should now be running on port 3000. Navigate to http://localhost:3000 in your web browser, and you should see the "Hello, World!" message.

Building a Basic Web Application with Node.js and Express.js

With your simple web server up and running, let’s expand your application by adding more routes and serving static files:

Create a new directory called public in your project folder.
Inside the public folder, create an HTML file called index.html with the following content:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Node.js and Express.js App</title>
</head>
<body>
    <h1>Welcome to our Node.js and Express.js App!</h1>
    <p>This is a simple web application built with Node.js and Express.js.</p>
</body>
</html>

Configure your Express application to serve static files from the public directory:

app.use(express.static('public'));

Add a new route for the /about page:

app.get('/about', (req, res) => {
  res.send('<h1>About Us</h1><p>We are a team of developers passionate about Node.js and Express.js.</p>');
});

Now, restart your application by stopping the previous node app.js command (Ctrl + C) and running it again. Navigate to http://localhost:3000 in your web browser to see the contents of index.html. You can also visit http://localhost:3000/about to view the About Us page.

Final app.js Code:

const express = require('express');
const app = express();

// Define a route for the root URL
app.get('/', (req, res) => {
  res.send('Hello, World!');
});

// Set the application to listen on a specific port
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

// Serve static files from the public directory
app.use(express.static('public'));

// Add a new route for the /about page
app.get('/about', (req, res) => {
  res.send('<h1>About Us</h1><p>We are a team of developers passionate about Node.js and Express.js.</p>');
});

Conclusion

In this article, we introduced the basics of getting started with Node.js and Express.js. We showed you how to set up a development environment, create a simple web server, and build a basic web application with multiple routes and static file serving. With this foundation, you can continue to explore the powerful features of Express.js and create more complex web applications with ease.