Introduction to Node.js and Express.js

Node.js is a JavaScript runtime built on Chrome's V8 JavaScript engine that allows developers to create scalable and high-performance server-side applications. Express.js is a popular Node.js framework that provides a flexible and modular way to build web applications.

Step 1: Install Node.js and Express.js

To get started, you need to install Node.js and Express.js on your machine. You can download the latest version of Node.js from the official Node.js website. Once you have installed Node.js, you can install Express.js using npm by running the following command:

npm install express

Step 2: Create a New Express.js Project

Create a new directory for your project and navigate to it in your terminal. Then, create a new file called app.js and add the following code:

const express = require('express');
const app = express();
const port = 3000;

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

app.listen(port, () => {
  console.log(`Server started on port ${port}`);
});

Step 3: Run the Application

To run the application, navigate to the project directory in your terminal and run the following command:

node app.js

Open a web browser and navigate to http://localhost:3000 to see the 'Hello World!' message.

Conclusion

In this tutorial, you learned how to create a simple web server using Node.js and Express.js. You can build on this example to create more complex web applications.