# installed version
node -v
# start a node process
node
# window -> global# document -> process# to exit or ctrl + c twice
process.exit(0);# npm - installed version
npm -v
# to start a project (package.json) and use third party libraries
npm init
# to install lodash (third party library) and update package.json
npm install lodash --save
# to install yargs 11.0.0 (third party library) and update package.json
npm install [email protected] --save
# to install nodemon
npm install nodemon -g
# to start an app with nodemon, to exit ctrl + c
nodemon app.js