This example shows the top 10 most populous countries in 2019 as horizontal bars, using React and D3 to render SVG marks and channels. The data is loaded from a CSV via `d3.csv`, then visualized with `scaleBand` for the y-axis and `scaleLinear` for the x-axis. Axes are drawn manually with `xScale.ticks()`, while `rect` elements encode population values by length. The React component uses `useState` and `useEffect` to fetch and manage the data asynchronously.