This bar chart displays the top 30 countries by population in 2020, using horizontal bars sorted by country name. Built with React and D3 v5, it uses `scaleBand` for the y-axis, `scaleLinear` for the x-axis, and SVG rendering for the marks. Data is loaded via `csv` from a GitHub-hosted dataset, with population values multiplied by 1000. The chart includes custom axis components and formats tick labels using D3's `format` with SI prefixes, converting "G" to "B" for billions.