This example presents an interactive world map that toggles between Mercator, orthographic, and Albers USA projections. Users can drag to rotate the orthographic globe and click countries to switch projections, with the United States triggering a Mercator view. Built with d3-geo, topojson, and world-atlas data, it uses d3.geoPath for rendering countries and graticules, d3.drag for rotation, and d3.zoom for panning. The SVG output features styled country polygons with hover effects and smooth transition animations during projection changes.