This choropleth map colors countries by economic classification using a natural Earth projection with an ordinal spectral color scale. The visualization supports zooming and panning through d3.zoom, with country names and income groups revealed on hover via SVG title elements. A custom color legend with circles and text labels is built using D3 data joins, while geographic data comes from the world-atlas TopoJSON dataset processed with topojson.feature and loaded via d3.tsv and d3.json. The map is rendered entirely in SVG.