This example displays a horizontal bar chart of the top ten countries by population for 2020, using React to manage state and render the SVG, while D3 provides the scales and data loading. The chart uses `d3.scaleLinear` for the x-axis, `d3.scaleBand` for the y-axis categories, and `d3.csv` to fetch data from a GitHub Gist. Axis labels and tick marks are generated manually with React components and D3’s tick function, with no additional libraries beyond the core React 16.9 and D3 v5 APIs.