This example displays a world map rendered as black countries with white borders, which turn red on hover, with each country showing its name as a tooltip. It uses a Mercator projection via `d3.geoMercator` and `d3.geoPath` to draw the map, with geographic data from TopoJSON (world-atlas 50m) and country names from the accompanying TSV file. The map supports zooming and panning through `d3.zoom`, and renders entirely as SVG elements.