This choropleth maps sample population figures by country, joining an inline CSV to a world atlas via matching country names. The visualization uses D3 v7’s `geoNaturalEarth1` projection, `geoPath`, and `scaleSequential` with an YlGnBu interpolator, rendering graticules and country polygons as SVG paths. Tooltips appear on hover, and a TopoJSON (countries-110m.json) data source supplies the geometry.