Package Managers in JavaScript (npm vs Yarn)

Package managers are essential tools in modern JavaScript development. They allow you to install, update, remove, and manage third-party libraries or dependencies in your project.

The two most popular package managers are:

• npm (Node Package Manager)
• Yarn (developed by Facebook)

What is a Package?

A package is a prewritten JavaScript library or tool (e.g., React, Axios, Lodash) that you can install into your project using a package manager.

1. npm (Node Package Manager)

Installed automatically with Node.js

To check:

node -v
npm -v

Initialize a project:

npm init -y

Creates a package.json file that holds your project info and dependencies.

Install a package:

npm install axios

Install as a development dependency:

npm install eslint --save-dev

Remove a package:

npm uninstall axios

2. Yarn – Fast & Secure Alternative

Install Yarn:

npm install --global yarn

Initialize project:

yarn init -y

Add a package:

yarn add axios

Add dev dependency:

yarn add eslint --dev

Remove a package:

yarn remove axios

Files Created by npm/Yarn

Script Examples in package.json

"scripts": {
"start": "node index.js",
"lint": "eslint .",
"dev": "nodemon index.js"
}

Run with:

npm run start
# or
yarn start

npm vs Yarn – Key Differences