An interactive world map displays country boundaries with hover highlighting, rendered in SVG using the Natural Earth projection. The visualization loads GeoJSON from the World Atlas TopoJSON dataset and merges ISO country codes with name labels from a TSV file. Users can pan and zoom via `d3.zoom`. The code demonstrates `d3.geoPath` with `geoNaturalEarth1`, `topojson.feature`, and CSS transitions for hover effects.