Package is a term used by npm to denote tools that developers can use for their projects. This includes everything from libraries and frameworks such as jQuery and AngularJS to task runners such as Gulp.js. The packages will come in a folder typically called node_modules, which will also contain a package.json file. This file contains information regarding all the packages including any dependencies, which are additional modules needed to use a particular package.
Npm uses the command line to both install and manage packages, so users attempting to use npm should be familiar with basic commands on their operating system i.e.: traversing directories as well as being able to see the contents of directories.
Note that in order to install packages, you must have NPM installed.
The recommended way to install NPM is to use one of the installers from the Node.js download page. You can check to see if you already have node.js installed by running either the npm -v or the npm version command.
After installing NPM via the Node.js installer, be sure to check for updates. This is because NPM gets updated more frequently than the Node.js installer. To check for updates run the following command:
npm install npm@latest -g
To install one or more packages use the following:
npm install <package-name>
# or
npm i <package-name>...
# e.g. to install lodash and express
npm install lodash express
Note: This will install the package in the directory that the command line is currently in, thus it is important to check whether the appropriate directory has been chosen
If you already have a package.json file in your current working directory and dependencies are defined in it, then npm install will automatically resolve and install all dependencies listed in the file. You can also use the shorthand version of the npm install command which is: npm i
If you want to install a specific version of a package use:
npm install <name>@<version>
# e.g. to install version 4.11.1 of the package lodash
npm install [email protected]
If you want to install a version which matches a specific version range use:
npm install <name>@<version range>
# e.g. to install a version which matches "version >= 4.10.1" and "version < 4.11.1"
# of the package lodash
npm install lodash@">=4.10.1 <4.11.1"
If you want to install the latest version use: