Describing UI structures
JSX is the best way to describe complex UI structures. Let's look at some JSX markup that declares a more elaborate structure than a single paragraph:
import React from 'react'; import { render } from 'react-dom'; // This JSX markup describes some fairly-sophisticated // markup. Yet, it's easy to read, because it's XML and // XML is good for concisely-expressing hierarchical // structure. This is how we want to think of our UI, // when it needs to change, not as an individual element // or property. render(( <section> <header> <h1>A Header</h1> </header> <nav> <a href="item">Nav Item</a> </nav> <main> <p>The main content...</p> </main> <footer> <small>© 2016</small> </footer...