. Hello, world!

React Application Directory

SRC → Index.js (Its our project entry point, whenever we open react app index.jss will run first like a door to enter into the room)

Public → Index.html (Where we display our front end elements)

SRC → App.js (its a component, here we manage different components)

SRC → App.js and APP.css

 

here is the concept 

first index.js run and it will get components from app.js and the it will render componetns in index.html to display components to end user