npm Useful commands

npm init :

create your package.json file automatically

npm install [--save-dev] [package_name]:

1. Retrieves the last version of a package

2. Install itglobally, for production environment or for development environment

eg: npm 安装webpack：npm install --save-dev webpack

npm install:

Install all the packages defined in your package.json file

npm run [script_name]

1. Runs the right command lines defined in the scripts section

2. For “start” or “test” commands, keyword “run” is not needed