A world map rendered as an SVG uses D3’s `geoNaturalEarth1` projection and `geoPath` to draw landmasses, graticules, and sphere outlines. The land is filled in blue, with gray interior borders, graticules, and sphere background. Data comes from the `world-atlas` TopoJSON file, processed with `feature` and `mesh` from `topojson`. The React component loads the data via `useEffect` and `json`, then passes it to the marks for rendering.