This bar chart displays the populations of 30 countries for 2020, with countries listed along the vertical axis and population values extending horizontally. The visualization uses React and D3 v5, implementing custom `AxisBottom`, `AxisLeft`, and `Marks` components to render SVG elements. Population data is loaded via d3.csv, with values formatted using d3.format. Bars appear in green (#90ee90), while axes and labels use muted grays. The chart includes hover tooltips showing formatted population values, and the x-axis label indicates "POPULATION-2020".