A horizontal bar chart displays the 20 most populous countries in 2010, with each bar labeled by country name and scaled by population in billions. The visualization uses React components with D3 v5 utilities, including `scaleBand` for the categorical y-axis and `scaleLinear` for the quantitative x-axis. Data is loaded asynchronously from a CSV file via `d3.csv`, and SVG rectangles render the bars with tooltips showing formatted population values. Axes are built from custom React components that map D3 scales to SVG elements.