How to Install Node js on Ubuntu

What is Node.js?

Node.js is an open-source, cross-platform runtime environment that lets you run JavaScript on the server.

• Works with Node Package Manager (npm)
• Used for both frontend and backend development
• Popular for building fast, scalable web applications

Express.js is a lightweight framework for Node.js, perfect for building APIs and websites.

Prerequisites

Before you start installing Node.js on Ubuntu 20.04:

• Have a fully updated Ubuntu 20.04 server
• Create a non-root user with sudo privileges

How to Install Node.js on Ubuntu?

Step 1: Install Node.js on Ubuntu 20.04

There are several methods to install Node.js on Ubuntu. You can:

• Install from the official Ubuntu repository (stable version)
• Install from NodeSource PPA (newer versions)
• Install with NVM (Node Version Manager) for flexibility

1.1 Install Node.js from Ubuntu Repository

This method provides a stable release but not always the latest version.

sudo apt update
sudo apt install nodejs -y
sudo apt install npm -y

Check the installed versions:

node -v
npm -v

Now you have Node.js installed on Ubuntu with npm.

1.2 Install Node.js via NodeSource PPA

If you need the latest Node.js version, use the NodeSource PPA. Download and install Node.js 16.x (replace 16.x with another version if needed):

curl -sL https://deb.nodesource.com/setup_16.x | sudo -E bash -
sudo apt install nodejs -y

Check versions:

node -v
npm -v

This method is recommended if you want Node.js for Ubuntu with the latest features.

1.3 Install Node.js via NVM

NVM allows you to manage multiple Node.js versions on the same server.
Install NVM:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.1/install.sh | bash

Verify installation:

nvm -v

List available Node.js versions:

nvm ls-remote | more

Install the latest Node.js:

nvm install node

Or install a specific version (example v16.15.0):

nvm install 16.15.0

Switch between versions:

nvm use 18.2.0

Best option if you want flexibility in Node.js install on Linux.

Step 2: Install Express.js

Now that Node.js is installed, let’s install Express.js and create a simple app.

2.1 Install Express globally

npm install -g express

2.2 Create a new project

mkdir myproject
cd myproject
npm init -y
npm install express

2.3 Create an app.js file

nano app.js

Add this Hello World example:

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

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

app.listen(port, () => {
  console.log(`App running at http://localhost:${port}`)
})

Run the app:

node app.js

Step 3: Access Your Express App

By default, the app runs on http://Server-IP:3000.
Open your browser and visit:

http://your-server-ip:3000

You should see Hello World!

Conclusion

Congratulations! You now know how to:

• Download and install Node.js on Ubuntu 20.04
• Use different methods (Ubuntu repo, PPA, NVM)
• Verify if Node.js is installed
• Install and run an Express.js app

This guide works not only for Node.js Ubuntu installation, but also for general Node.js install in Linux servers.