This example shows a horizontal bar chart of the ten most populous countries in 2020, with countries listed on the y-axis and population totals on the x-axis. It combines React state management with D3 utilities, using `d3.csv` to load data and `scaleBand`, `scaleLinear`, and `max` to compute positions and scales. React renders the SVG elements, while D3 generates the tick marks and grid lines for both axes. The source data comes from a UN population dataset hosted as a CSV file.