This bar chart displays the population figures for 30 countries in 2020, using green bars arranged along a categorical y-axis with a quantitative x-axis. The visualization is built with React and D3 v5, rendering SVG elements through custom components for axes and marks. Population data is loaded from a remote CSV file using D3's `csv` function. The x-axis uses D3's `format` function to abbreviate large numbers, converting values to billions with the letter "B".