This example demonstrates a minimal React application that renders the text “Hello react” in a 166 by 166 pixel viewport. It serves as a starter template for building interactive data visualizations. The code loads React 18.3.1 and ReactDOM from a CDN, along with D3 version 7.9.0, though D3 is not yet used in this initial setup. The `ReactDOM.render` method mounts the `App` component into the root div, establishing the basic structure for future data-driven charts.