A horizontal bar chart shows the top 10 countries by 2019 population, ranked by number of units or items purchased. The visualization is rendered as an SVG using React with D3, leveraging `d3.csv` for data loading, `d3.scaleBand` for the y-axis, `d3.scaleLinear` for the x-axis, and `d3.max` to determine the domain. Each bar’s length encodes the population value, with axis ticks and labels generated via D3’s scale methods. The code fetches data from a Gist URL and uses React’s `useState` and `useEffect` to manage the asynchronous data loading.