This bar chart displays the top 10 most populous countries from the United Nations World Population Prospects 2019 dataset. Built with React and D3 v5, it uses SVG rendering to draw horizontal bars representing each country's population. The code separates concerns into reusable components for axes and marks, with D3's `scaleBand` and `scaleLinear` handling the coordinate mappings. Data is loaded asynchronously using D3's `csv` function and the first ten rows are selected for display.