npm install meaning code example

Example 1: install node modules

// Install as a dependency
npm install --save packageName
// OR
npm install --save package1 package2
// OR
npm install --save package@version
// OR
npm i -s packageName

// Install as a dev-dependency
npm install --save-dev package@version
// OR
npm i -D packageName

//Install globally
npm install --global packageName
//OR
npm i -g packageName

// You might need SU access on macos/linux to install globally

Example 2: what is npm install

npm install module-name
npm i module-name
puts module-name package (js library file) 
into node_modules folder
so you can require it in node app