This example shows population data for 20 countries as a horizontal bar chart. The bars’ lengths encode each country’s population value, with country names on the y-axis and a bottom axis formatted in billions. Built with React and D3 v5, it uses `scaleBand` for the y-axis, `scaleLinear` for the x-axis, and SVG `rect` elements. The CSV data is loaded via `d3.csv`, and tooltips display the formatted population using the D3 `format` API.