This example presents two interactive choropleth maps side by side: a world map visualizing population data using a Natural Earth projection, and a United States map displaying crime rates via an Albers USA projection. Both maps use D3 v7 and TopoJSON to render SVG paths, with sequential color scales (blue for population, green for crime) encoding numeric values. Hovering over a country or state triggers a tooltip showing the region name and its corresponding statistic. The code loads GeoJSON from world-atlas and us-atlas packages accessed via CDN.