This example presents a world map visualization using the Mercator projection, with each country rendered as an SVG path. The countries are initially filled teal with white borders, and hovering over a country turns it yellow, while moving the mouse away changes it to light green. The code loads geographic data from the world-atlas TopoJSON file and converts it to GeoJSON using the topojson library. It leverages D3.js v6 APIs including `d3.geoMercator`, `d3.geoPath`, and SVG `path` elements for rendering, with mouse events handled via D3's `.on()` method.