A choropleth map colors countries by economic category using an ordinal color scale with a spectral palette. The visualization loads world geometry and country metadata from the world-atlas TopoJSON and TSV files, rendering paths with `d3.geoPath` and a Natural Earth projection. Users can pan and zoom via `d3.zoom`, while a custom legend built with D3 selections displays color categories as circles and text. Hovering highlights a country in red, and tooltips show each nation's name and economy type.