This example shows a world map of all countries rendered as grey SVG paths with black borders on a yellow background. It uses D3 v5's `geoNaturalEarth1` projection and `geoPath` to generate the geographic shapes. Country boundaries come from a TopoJSON file loaded from the world-atlas dataset via a URL, processed with the `topojson.feature` API. The code fetches the data asynchronously with `json()`, then appends each country as a `path` element to the SVG canvas.