When you install a package using npm into your node_modules folder, or also globally, how do you use it in your Node code?

Say you install lodash, the popular JavaScript utility library, using

npm install lodash

This installs the package in the local node_modules folder.

To use it in your code, you just need to import it into your program using require:

const _ = require('lodash')

What if your package is an executable?

In that case, the executable is placed in node_modules/.bin/.

For example, cowsay provides a CLI:

The cowsay package provides a command line program that can be executed to make a cow say something (and other animals as well 🦊).

Running npm install cowsay installs the package and its dependencies in node_modules:

There is a hidden .bin folder, which contains symbolic links to the cowsay binaries:

How do you execute those?

You can run ./node_modules/.bin/cowsay, but npx (included in npm since 5.2) is simpler:

npx cowsay

npx finds and runs the package.

Lessons in this unit:

0:	Introduction
1:	▶︎ How to use or execute a package installed using npm
2:	npm dependencies and devDependencies
3:	How to fix the "Missing write access" error when using npm
4:	npm can install packages in the parent folder
5:	Install an older version of an npm package
6:	Find the installed version of an npm package
7:	How to test an npm package locally
8:	npm global or local packages
9:	What are peer dependencies in a Node module?
10:	`npm run dev` is a long-running program
11:	Semantic Versioning using npm
12:	Uninstalling npm packages with `npm uninstall`
13:	An introduction to the npm package manager
14:	The npx Node Package Runner
15:	The package.json guide
16:	The package-lock.json file
17:	What is pnpm?
18:	Should you commit the node_modules folder to Git?
19:	Update all the Node dependencies to their latest version
20:	Where does npm install the packages?
21:	Bumping Node.js dependencies
22:	Run package.json scripts upon any file changes in a folder