This example shows the top 10 most populous countries as a horizontal bar chart, using population data from the United Nations World Population Prospects 2019. The chart displays country names on the y-axis and population counts on the x-axis, with steel-blue bars and a headline title. It uses React for the component structure and D3 v5 APIs including `csv`, `scaleLinear`, `scaleBand`, `axisLeft`, and `axisBottom` to load data, scale values, and render axes. The visualization is rendered as SVG within a fixed 960×500 viewport, with formatted tick labels converting values to billions.