create-react-app build code example

Example 1: create react app

npx create-react-app my-app
cd my-app
npm start

Example 2: how to create react app using yarn

yarn create react-app my-app

Example 3: new create react app

npx create-react-app my-app
cd my-app
npm start
//Note:npx on the first line is not a typo — 
//it’s a package runner tool that comes with npm 5.2+.

Example 4: create-react-app npm yarn

to override yarn
npx create-react-app my-app --use-npm

Example 5: build react app

Build a react project
Code has to be bundled using a bundler like webpack and
 transformed using a compiler like Babel.
do production optimizations such as code splitting(critical CSS)
statically pre-render some pages for performance and SEO. 
use server-side rendering or client-side rendering.
write some server-side code to connect your React app to your data store.
OR use create-react-app

Example 6: react app using npm

npx create-react-app app-name
cd app-name
npm start