This example displays the top 10 most populous countries as a bar chart with no axes or labels, using rectangles whose widths encode population values. The code loads United Nations World Population Prospects 2019 data via `d3.csv`, processes it with a custom row function, and renders SVG bars using React state and hooks. It employs `d3.scaleBand` for vertical positioning and `d3.scaleLinear` for horizontal scaling, all within a React component that manages data loading through `useEffect`.