A horizontal bar chart displays the top 10 most populous countries from the United Nations World Population Prospects 2019 dataset. The bars are styled with a teal fill and labeled axes in the Poppins font. Built with React and D3 v5, it uses `d3.csv` for data loading, `scaleBand` and `scaleLinear` for positioning, and SVG `<rect>` elements for rendering. A formatted `d3.format` function converts population values to billions with a 'B' suffix.