This example displays a horizontal bar chart of 2020 population estimates for the top 10 countries, sourced from UN Population Prospects data loaded via d3.csv (d3-fetch). The React 17 app uses d3.scaleBand for the country axis and d3.scaleLinear for population, rendering SVG rectangles with native `<title>` tooltips. Axes are built manually through React components (AxisBottom, AxisLeft), while d3.format formats population values with SI notation, converting 'G' to 'B'. The chart is styled with a teal fill and Poppins font.