This example demonstrates how to load and summarize a CSV dataset using React state and D3 utilities. The app fetches iris flower data from a remote URL via `d3.csv`, storing the parsed result with React's `useState` and `useEffect` hooks. While loading, it displays "Loading...", then renders a plain-text summary describing the data's size in kilobytes, row count, and column count using `d3.csvFormat` and the dataset's `columns` property. The visualization is minimal—a styled `<pre>` element—focusing on the integration of React's component lifecycle with D3's data-loading API.