A world map rendered in the Mercator projection displays country boundaries as grey paths with thin white strokes. The example demonstrates loading GeoJSON-derived topology data from a local `world-110m2.json` file and converting it to SVG paths using `d3.geoPath`. The map is centered and rotated with `d3.geoMercator` and `projection.rotate`, and country features are extracted via `topojson.feature` from the TopoJSON library. The page uses D3 v7 to fetch the data asynchronously with `d3.json` and append the resulting paths to an SVG container.