Installing Node.js and npm

Before you can use npm, you need to install Node.js. npm comes bundled with Node.js, so you'll get both with a single installation.

Installation Methods

There are several ways to install Node.js:

Method 1: Official Installer (Recommended for Beginners)

1. Visit nodejs.org
2. Download the LTS (Long Term Support) version
3. Run the installer and follow the prompts
4. Restart your terminal

Method 2: Node Version Manager (Recommended for Developers)

Using a version manager like nvm (Node Version Manager) lets you easily switch between Node.js versions.

On macOS/Linux:

# Install nvm
curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.0/install.sh | bash

# Install latest LTS version
nvm install --lts

# Use the installed version
nvm use --lts

On Windows:

Use nvm-windows:

# After installing nvm-windows
nvm install lts
nvm use lts

Method 3: Package Managers

macOS (Homebrew):

brew install node

Ubuntu/Debian:

curl -fsSL https://deb.nodesource.com/setup_lts.x | sudo -E bash -
sudo apt-get install -y nodejs

Windows (Chocolatey):

choco install nodejs-lts

Verifying Your Installation

After installation, open a new terminal window and run:

node --version
# Should output something like: v20.10.0

npm --version
# Should output something like: 10.2.3

If both commands show version numbers, you're ready to go!

Understanding the Versions

Component	Current LTS	Purpose
Node.js	v20.x or v22.x	JavaScript runtime
npm	v10.x	Package manager

LTS vs Current:

• LTS (Long Term Support): Stable, recommended for most users
• Current: Latest features, may be less stable

Common Installation Issues

"command not found: npm"

This usually means:

1. Node.js isn't installed properly
2. The installation path isn't in your system PATH
3. You need to restart your terminal

Fix: Close and reopen your terminal, or restart your computer.

Permission Errors on macOS/Linux

If you see EACCES permission errors:

# Fix npm permissions (recommended)
mkdir ~/.npm-global
npm config set prefix '~/.npm-global'
# Add to your ~/.bashrc or ~/.zshrc:
export PATH=~/.npm-global/bin:$PATH

Multiple Node Versions Conflict

If you have multiple installations:

# Check which node is being used
which node

# Check all installed versions (if using nvm)
nvm list

Your First npm Command

Let's verify npm works by checking the registry:

npm ping
# Should output: Ping success: {...}

You can also see all available npm commands:

npm help

Practice: Version Check

The commands below show how to check your Node.js and npm versions:

npm Configuration

npm stores its configuration in several places:

# View all npm config settings
npm config list

# View a specific setting
npm config get registry

# Set a configuration value
npm config set init-author-name "Your Name"

Common configuration options:

Setting	Description	Default
registry	Package registry URL	https://registry.npmjs.org/
prefix	Global package install location	System-dependent
cache	Package cache location	~/.npm

Key Takeaways

1. Download from nodejs.org for the simplest installation
2. Use nvm if you need multiple Node.js versions
3. Verify installation with node --version and npm --version
4. LTS versions are recommended for stability
5. Fix permission issues by configuring npm's prefix

What's Next?

Now that you have npm installed, let's dive into the most important file in any npm project: package.json.