Frontend V/S Backend And API V/S JSON

Frontend

when you open a website in browser the visible part of screen is User Interface. Browser has an ability to send or receive request from server,It has an engine to execute Javascript. HTML is like a skeleton, Css give style, javascript gives actions.

Backend

The huge dynamic data stored in database. The frontend request for data in backend using API.

API

API is a pice of code helps to interact with database data on the internet.

JSON

JSON format has a key value pair data format, it is an efficient data format to transfer data between frontend to backend.