This example displays the top 10 countries by United Nations population estimates for 2020 as horizontal bars, using React to render SVG rectangles and D3 scales for layout. It loads data from a CSV file via `d3.csv`, parses the population column, and maps countries to a `scaleBand` y-axis and populations to a `scaleLinear` x-axis. React’s `useState` and `useEffect` manage the asynchronous data fetching, while `ReactDOM.render` mounts the visualization. The chart updates when data arrives, though it does not include axes or labels.