Npm in NodeJs
Great question! Let’s break down NPM (Node Package Manager) — a core part of working with Node.js 🚀
📦 What is NPM?
NPM is the default package manager for Node.js.
It helps you:
📥 Install libraries (aka packages/modules)
⚙️ Manage project dependencies
🚀 Publish your own packages (if you want!)
✅ Check NPM Version
npm -v
🛠 Common NPM Commands
| Command | What It Does |
|---|---|
npm init | Create a new package.json (manual setup) |
npm init -y | Auto-generate default package.json |
npm install <package> | Install a package locally |
npm install -g <package> | Install a package globally |
npm uninstall <package> | Remove a package |
npm update | Update all dependencies |
npm list | List installed packages |
📁 package.json – What’s Inside?
This file tracks your project's dependencies, version, scripts, and more.
{ "name": "my-app", "version": "1.0.0", "dependencies": { "express": "^4.18.2" }}
📥 Installing a Package Example
npm install express
✅ Adds express to:
node_modules/package.json→ under"dependencies"
🧼 Install Dev-Only Packages
Use --save-dev for things like testing or building tools:
npm install nodemon --save-dev
➡️ Goes into "devDependencies"
💡 Run Scripts with npm
Inside package.json:
"scripts": { "start": "node app.js", "dev": "nodemon app.js"}
Then run:
npm run startnpm run dev
🌍 Using Global Packages
Install tools like nodemon or http-server globally:
npm install -g nodemon
Then you can run nodemon app.js from anywhere.
📚 NPM Registry
You can search or explore packages on:
🌐 https://www.npmjs.com
