A world map visualization displays country boundaries as filled shapes on a light gray sphere, using an equal-earth projection. The map is rendered with SVG, where each country path is drawn via `d3.geoPath` and the projection is set with `geoEqualEarth`. Data comes from the world-atlas TopoJSON dataset, processed through `topojson.feature` to extract country geometries. The React-based example uses the `useData` hook to asynchronously load and transform the data before rendering.