This bar chart shows the top 10 countries by total population for 2020, based on the World Population Prospects 2019 dataset. The visualization uses React and D3 v5, with SVG rectangles to encode population values horizontally. Axes are rendered via the `scaleBand` and `scaleLinear` D3 scales. The `<title>` element provides simple, browser-native tooltips, and the chart uses D3's `format` for tick labels, converting Giga to Billions.