A Complete Guide - Installing Nodejs and npm

1. What is Node.js?

Answer: Node.js is a JavaScript runtime built on Chrome's V8 JavaScript engine. It allows developers to run JavaScript code outside the browser, enabling them to build scalable network applications. Node.js uses an event-driven, non-blocking I/O model which makes it lightweight and efficient.

2. What is npm?

Answer: npm (Node Package Manager) is the package manager for Node.js. It facilitates the installation, updating, and managing of Node.js packages and their dependencies. npm is the default package manager for Node.js and is included when you install Node.js.

3. How do I install Node.js and npm on Windows?

Answer:

5. How do I install Node.js and npm on Linux?

Answer:

• Using Package Manager (Ubuntu):

1. Update your package manager: sudo apt update.
2. Install Node.js and npm: sudo apt install nodejs and sudo apt install npm.
3. Verify the installation by typing node -v and npm -v in the terminal.

• Using NodeSource Binary Distributions:

1. Install NodeSource PPA (you can choose your Node.js version, e.g., Node 16.x): curl -fsSL | sudo -E bash -.
2. Install Node.js and npm: sudo apt-get install -y nodejs.
3. Verify the installation as above.

6. How do I install a specific version of Node.js?

Answer:

• Using n (Node version manager):

1. Install n globally: sudo npm install -g n.
2. Install a specific version: sudo n 16.14.0 (replace 16.14.0 with your desired version).
3. Verify the installation with node -v.

• Using NodeSource (Linux):

1. Remove any existing Node.js installations.
2. Follow the instructions for installing from NodeSource to choose a specific version (as outlined in Question 5).

7. How do I check the installed versions of Node.js and npm?

Answer: You can easily check the versions of Node.js and npm installed on your system by running the following commands in the terminal:

• node -v to get the Node.js version.
• npm -v to get the npm version.

8. How do I update Node.js and npm?

Answer:

• Node.js:

1. Windows/macOS:
   • Uninstall the current version and reinstall the latest version using the installer.
2. Linux:
   • Depending on the method used, update using package manager commands (e.g., sudo apt-get update and sudo apt-get install nodejs for Ubuntu).

• npm:

1. Run the following command to update npm globally: npm install -g npm.

9. How do I uninstall Node.js and npm?

Answer:

• Windows:

1. Uninstall Node.js through the Control Panel: Programs and Features > Uninstall a program.
2. Optionally, remove node_modules from your user profile or project directory to clear npm cache.

• macOS/Linux:

1. Use your system's package manager to remove Node.js and npm.
   • For example, sudo apt-get remove nodejs npm for Ubuntu.
2. Manually remove node and npm if necessary:

   sudo rm -rf /usr/local/bin/{node,npm}
   sudo rm -rf /usr/local/lib/node*
   sudo rm -rf /usr/local/include/node*
   sudo rm -rf /usr/local/share/man/man1/node*
   sudo rm -rf ~/.npm
   

10. What are some common issues and how can they be resolved during Node.js and npm installation?

Answer:

• npm: EACCES permission error:
  • Use sudo before your npm commands, or change the npm default directory: mkdir ~/.npm-global followed by npm config set prefix '~/.npm-global'.
• Node.js installation doesn’t work from command line:
  • Reinstall Node.js and ensure you select the option to add Node.js to your PATH during installation.
• npm install fails due to missing dependencies:
  • Ensure you have a stable Internet connection. You can also try clearing npm cache with npm cache clean --force and then retry.