← React Beginner Questions - Set 1 Q1

What is React?

React Beginner Questions - Set 1

The smallest complete React app: one component, mounted into a DOM node. Everything else in React is a variation on this.

Example

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import { createRoot } from 'react-dom/client';

function App() {
  return <h1>Hello from React</h1>;
}

const root = createRoot(document.getElementById('root'));
root.render(<App />);

What to notice

• React is a library, not a framework: it renders UI and leaves routing, data fetching and state management to other packages.
• The return value of a component is a description of the UI, not DOM nodes. React turns it into DOM for you.
• No jQuery-style DOM updates anywhere — the only imperative call is the one that mounts the app.