This example shows a full-screen React application displaying a single large message, "Hello World," centered vertically and horizontally in the browser window. The interface is minimal, with no interactive controls or dynamic elements. The application is built using React 16.13.1 for component rendering and ReactDOM to mount the root component into the DOM. The code relies on the production builds of both libraries loaded from a CDN, with a separate `bundle.js` file containing the transpiled application logic.