This bar chart displays the population of 30 countries for the year 2020, sorted along a horizontal axis using a linear scale. The vertical axis lists country names via a band scale. Data is loaded as CSV and formatted with d3’s `format` for tick labels (converting billions). The visualization uses React with d3.v5, rendering as SVG with custom `AxisBottom`, `AxisLeft`, and `Marks` components. Each bar includes a tooltip showing the formatted population value.