To publish and install packages to and from the public npm registry, you must install Node.js and the npm command line interface using either a Node version manager or a Node installer. We strongly recommend using a Node version manager to install Node.js and npm. We do not recommend using a Node installer, since the Node installation process installs npm in a directory with local permissions and can cause permissions errors when you run npm packages globally.
To see if you already have Node.js and npm installed and check the installed version, run the following commands:
node -v npm -v
Node version managers allow you to install and switch between multiple versions of Node.js and npm on your system so you can test your applications on multiple versions of npm to ensure they work for users on different versions.
If you are unable to use a Node version manager, you can use a Node installer to install both Node.js and npm on your system.
If you're using OS X or Windows, use one of the installers from the Node.js download page. Be sure to install the version labeled LTS. Other versions have not yet been tested with npm.
If you're using Linux or another operating system, use one of the following installers:
Or see this page to install npm for Linux in the way many Linux developers prefer.
For more information on installing Node.js on a variety of operating systems, see this page.