A horizontal bar chart displays the populations of 20 countries in 2010, with bars sorted by country name along the y-axis and population values on the x-axis. The chart is built with React and D3 v5, using `scaleBand` for the categorical y-axis, `scaleLinear` for the quantitative x-axis, and `format` to abbreviate tick labels (e.g., showing "1.2B" instead of 1,200,000,000). Data is loaded from a CSV file via `d3.csv` and rendered as SVG rectangles with hover tooltips.