This example displays the top 10 most populous countries as a horizontal bar chart, with country names on the y-axis and population in billions on the x-axis. The React application uses d3.csv to load United Nations World Population Prospects 2019 data, d3.scaleBand for the categorical axis, and d3.scaleLinear for the quantitative axis. SVG rectangles render the bars via the Marks component, while custom axis components generate ticks and labels.