Install the package with npm install / yarn add

Premise

Reference: Npm and yarn command quick reference table

• If I installed the package using npm or yarn, where is it stored? * ** Saved to installed in global environment or installed in local environment **

What is the global environment?

System common directory, node global environment Used when installing tools and commands used in the entire system

What is a local environment?

The environment in the application (project) that I made For the added package, describe "Which package to install" in package.json in the application (project). Used when installing packages used for each application

Install in global environment

The package is installed in the global environment of node ** -g option means global environment ** ** install can be omitted with i ** npm

npm install -g Package name

//The following is also OK

npm i -g Package name

yarn

yarn global add package name

Install to local environment

Add --save to install to local environment Once installed, it will be added to dependencies in the package.json file npm

npm install --save package name

yarn

yarn add package name

Install the development package in your local environment

Add --save-dev when installing Once installed, it will be added to devDependencies in the package.json file ** --save-dev can be omitted with -D ** npm

npm install --save-dev package name

//The following is also OK

npm i -D Package name

yarn

yarn add --dev package name

Tips

• When you are doing team development on github or gitlab, a new package is introduced, but it is not set in your local environment yet * ** [Conclusion] After git pulling to your local repository, install the settings described in the package.json file **

$ git pull origin master

//If you are developing on npm
$ npm install

//If developing with yarn
$ yarn install