A horizontal bar chart ranks the top 10 most populous countries from the UN World Population Prospects 2019 dataset, with population values formatted in billions. Built with React and D3 v5, it uses `scaleBand` for the categorical y-axis and `scaleLinear` for the population x-axis, rendering SVG `<rect>` marks with native `<title>` tooltips. Axis components map ticks using D3’s scale methods, and the chart is styled with Poppins font and a teal color scheme.