This example displays two static choropleth-style maps: a world map using the Natural Earth projection and a US states map using the Albers USA projection. It demonstrates how to load TopoJSON data from the `world-atlas` and `us-atlas` datasets, convert it to GeoJSON with `topojson.feature`, and render it with `d3.geoPath` and `d3.geoNaturalEarth1` or `d3.geoAlbersUsa`. Both maps include graticule lines and interactive title tooltips showing region IDs.