Node.js — Server-side JavaScript Study Material

Node.js is a free, open-source, cross-platform JavaScript runtime environment that allows developers to execute JavaScript code outside of a web browser. It is primarily used to build fast, scalable, and high-performance server-side network applications

1. Node.js Installation

Installing Node.js is the first step for any developer. While you can download a direct installer from the official website, professional setups often prefer version managers to avoid permission issues and allow for flexibility.

LTS vs. Current:
- LTS (Long Term Support): Recommended for most users. It’s stable and receives security updates for years.
- Current: Includes the latest features but may be less stable.
The Ecosystem: Installing Node.js automatically installs npm (Node Package Manager), which is essential for managing external libraries.

https://nodejs.org/en/download

2. Node Version Managers (NVM)

In a professional setting, you might work on one project that requires Node 16 and another that requires Node 20. Version managers allow you to switch between them instantly.

Popular Tools

nvm (Node Version Manager): The industry standard for macOS and Linux.
nvm-windows: The most popular choice for Windows users.
fnm (Fast Node Manager): A newer, extremely fast alternative built in Rust.

Why use a Version Manager?

Project Isolation: Prevents "it works on my machine" bugs by ensuring every developer uses the same version.
No Sudo Required: Avoids using sudo for global installs on Linux/macOS, which is a major security plus.
Easy Upgrades: Test your app on a new Node version with a single command before committing to an upgrade.

3. Key Commands (Cheat Sheet)

Below are the "must-know" commands:

Command	Description
node -v	Checks the currently installed Node version.
nvm install [version]	Downloads and installs a specific version.
nvm use [version]	Switches the active Node version for the current terminal.
nvm list	Shows all Node versions currently installed on the machine.