This example demonstrates how to load and summarize CSV data using D3 and React. It shows a simple text message reporting the data's file size in kilobytes, row count, and column count. The app uses React hooks (`useState` and `useEffect`) to fetch data from a GitHub gist via `d3.csv` and `d3.csvFormat` to calculate the metrics. The visualization is minimal, presenting only the computed statistics in a large `<pre>` element.