A minimal React starter demo renders a static "Hello React!" message centered on the page. The app uses `ReactDOM.render` to mount a functional component into the `#root` element, with styling controlled by a CSS class. React 16.13.1 and ReactDOM are loaded from unpkg CDN, while the entry point is `index.js` and the bundled output is `bundle.js`. No interaction, data, or charting libraries are present; it simply demonstrates the basic setup for a React-based visualization project.