This example displays the top 10 most populous countries as horizontal bars, with country names on the left and numeric population values along the bottom axis. It loads UN population data from 2019 using `d3.csv`, then renders the chart as SVG through React components. The code uses D3’s `scaleBand` for the y-axis, `scaleLinear` for the x-axis, and manually draws tick lines and labels for both axes. React state management and hooks coordinate the asynchronous data loading and conditional rendering.