This example visualizes the top 10 most populous countries using a bar chart with no axes, rendered as SVG elements. It loads population data from the United Nations World Population Prospects 2019 dataset via `d3.csv`, then uses React’s `useState` and `useEffect` hooks to fetch and store the data. The chart maps each country to a rectangle, sizing bars with `scaleBand` and `scaleLinear` from d3.v5, while the overall layout is managed through React and ReactDOM.