This example shows a basic interactive world map using D3.js and TopoJSON. It renders country outlines, a graticule grid, and a map outline using d3.geoPath with a geoNaturalEarth1 projection. Country boundaries are loaded from the visionscarto-world-atlas TopoJSON dataset via fetch and converted to GeoJSON with topojson.feature. The React-based rendering uses a small state machine to handle asynchronous data loading, then calls the map function to draw paths into an SVG.