Install Node.js modules
Node.js comes with the npm package manager. Using it, you can install, uninstall and search for Node.js modules.
npm installs modules in two different scopes: local and global.
The local installation is recommended, as the size of the packages is usually small. It installs the packages in a node_modules subdirectory of the current working directory, usually a project folder. This ensures all the required dependencies are installed and won’t break when installing other packages in a different project or locally.
To install modules locally, you just have to execute this command:
$ npm install PACKAGE
For example, to install MySQL, you would execute:
$ npm install mysql
In other cases (typically when the module installs a command line tool), it is more convenient to install the packages globally. In these cases, the command varies slightly:
$ sudo npm -g install PACKAGE
For example, to install Express, you would execute:
$ sudo npm -g install express
This will make the Express command-line available in all projects.
We recommend installing packages in both local and global modes, so that you can share installed commands and still protect the dependencies of your project.