Node.js Installation - Session 3 | AI Educators Course

⏱️ 20 minutes

The Engine Behind Claude Code

Node.js is the runtime environment that makes Claude Code work. Think of it as the engine in a car - you need it to make everything run, but you don't need to understand how it works internally!

🎯 Learning Objectives

Understand what Node.js is and why it's needed
Download the correct version for your system
Install Node.js with proper settings
Verify installation using PowerShell
Troubleshoot common installation issues

🤔 What is Node.js?

Node.js is a JavaScript runtime - software that lets your computer run JavaScript programs outside of web browsers.

Why Do We Need It?

Claude Code Requirement: Claude Code is built with Node.js and won't work without it
Package Manager (npm): Comes with npm, which installs and manages development tools
Industry Standard: Used by millions of developers worldwide
Free & Safe: 100% free, open-source, and trusted by major companies

What Gets Installed?

Node.js: The JavaScript runtime
npm: Node Package Manager (for installing tools)
PATH updates: Makes commands work from PowerShell

📥 Download Node.js

Choose the LTS (Long Term Support) version for stability:

🌐 Visit nodejs.org

Click the big green "LTS" button on the homepage

📦 Installation Walkthrough

Download the Installer

Go to nodejs.org
Click the large green button labeled "LTS" (e.g., "20.11.0 LTS")
The installer will download to your Downloads folder
File will be named something like node-v20.11.0-x64.msi (Windows) or node-v20.11.0.pkg (Mac)

Run the Installer (Windows)

Double-click the downloaded .msi file
Click "Next" on the welcome screen
Accept the license agreement → "Next"
Important: Keep the default installation folder → "Next"
Important: Select "Automatically install necessary tools" checkbox
Keep all default features selected → "Next"
Click "Install" (may ask for administrator permission - click "Yes")
Wait 2-3 minutes for installation
Click "Finish"

Run the Installer (Mac)

Double-click the downloaded .pkg file
Click "Continue" through the introduction
Accept the license → "Continue" → "Agree"
Keep standard installation location → "Install"
Enter your Mac password when prompted
Wait 2-3 minutes for installation
Click "Close"

Important: Restart PowerShell/Terminal

⚠️ Critical Step: You MUST close and re-open PowerShell/Terminal after installing Node.js for it to work!

Close all PowerShell or Terminal windows
Open a fresh PowerShell/Terminal window
Now you're ready to verify the installation

✅ Verify Installation

Open PowerShell (or Terminal on Mac) and run these commands:

Check Node.js Version

node --version

Expected output: v20.11.0 (or similar version number)

Check npm Version

npm --version

Expected output: 10.2.4 (or similar version number)

✅ Success! If you see version numbers for both commands, Node.js is installed correctly and ready to use!

🔧 Troubleshooting

Problem	Solution
"command not found" or "not recognized"	1. Close PowerShell completely 2. Re-open PowerShell 3. Try commands again If still not working, restart your computer
Permission denied error	Run PowerShell as Administrator: Right-click PowerShell → "Run as Administrator"
Old version showing	1. Uninstall old Node.js from Control Panel (Windows) or Applications (Mac) 2. Restart computer 3. Install new version
Installation fails	1. Disable antivirus temporarily 2. Run installer as Administrator 3. Check you have 500MB free disk space

💡 Understanding npm (Bonus Knowledge)

npm (Node Package Manager) was automatically installed with Node.js. Here's what it does:

Installs Tools: Like an app store for developer tools
Manages Updates: Keeps your tools up to date
Global vs Local: Can install tools system-wide (-g flag) or per-project

You'll use npm to install Claude Code in the next topic!

🎯 Quick Test Commands

Try these commands to explore Node.js:

1. Interactive Node.js Shell

node

Opens a JavaScript interactive shell. Type .exit to quit.

2. Check npm Configuration

npm config list

Shows npm settings and installation directory.

3. List Globally Installed Packages

npm list -g --depth=0

Shows what tools are installed globally (should be mostly empty for now).

✅ Topic Completion Checklist

✓ Understand what Node.js is and why it's needed
✓ Downloaded Node.js LTS version from nodejs.org
✓ Successfully installed with default settings
✓ Restarted PowerShell/Terminal
✓ Verified with node --version command
✓ Verified with npm --version command
✓ Both commands show version numbers

🚀 What's Next?

Now that Node.js is installed, you have everything you need to:

Install Claude Code CLI
Run AI-powered development tools
Build custom projects with AI assistance

But first, we need to set up your Anthropic Console account and get an API key!