A horizontal bar chart displays the population of 30 countries for 2020, with country names on the y-axis and population values on the x-axis. Rendered as SVG in a React framework using D3 v5, the chart uses `scaleBand` and `scaleLinear` to map data, and custom `AxisBottom` and `Marks` components built with React. Population values are formatted using D3's `format` with `siFormat`, converting billions to "B". Data is loaded asynchronously from a GitHub-hosted CSV via `useData` hook and D3's `csv` function.