This visualization displays the 2010 population of 20 countries as a horizontal bar chart, using a D3 scaleBand for the categorical country axis and a scaleLinear for the numeric population axis. The chart is rendered as SVG in React, with the population data fetched as CSV from a GitHub repository. Axis components generate tick marks and labels, while the Marks component draws green rectangles whose width encodes population, with a native SVG `<title>` tooltip showing the formatted value in billions.