This example visualizes the countries of the world as an SVG map using D3.js. It first renders a blue sphere as the ocean background, then projects country boundaries onto it using the Natural Earth dataset and a geoNaturalEarth1 projection. The map is constructed with the `geoPath` and `geoProjection` APIs, with `topojson.feature` processing the loaded GeoJSON data. Country shapes are filled in light green with a subtle black stroke, and the map is interactive only in the sense that it renders static geographic data.