Types of Packages and Installs

📥 Installing Packages

🔹 1. Local Installation (recommended)

• Installs the package only for your current project.

• Files land in the node_modules/ folder, and the package gets listed in package.json under dependencies.

• Keeps every project's dependencies isolated — no version conflicts between projects.

npm install lodash

✅ Usage:

const _ = require('lodash');

🔹 2. Global Installation

• Installs the package system-wide, not tied to any single project.

• Best for CLI tools you run from the terminal, like nodemon, http-server, or create-react-app.

npm install -g nodemon

⚠️ Not available via require() in your code — it's meant to be run as a command, not imported.

🔹 3. Dev Dependencies

• For tools only needed during development — testing, bundling, linting — not in production.

• Keeps your production build lean.

npm install --save-dev jest

📌 Listed separately in package.json under devDependencies.

🔹 4. Installing a Specific Version

• Useful when a project needs an exact version for compatibility.

npm install lodash@4.17.21

🔹 5. Uninstalling a Package

npm uninstall lodash

Add -g to remove a global package instead.

🔹 6. Reinstalling from package.json

• When you clone a project, dependencies aren't included — only listed.

• This command reads package.json and installs everything it needs.

npm install