This example shows a horizontal bar chart of the top ten countries by 2020 population, rendered as SVG with React. The code loads UN population data from a CSV file using `d3.csv` and transforms each row by parsing the “2020” field. React’s `useState` and `useEffect` manage data loading, while D3 scales `scaleLinear` and `scaleBand` map population values and country names to pixel positions. Each bar is a `<rect>` element generated by mapping over the data array inside a React component.