This interactive map uses a choropleth encoding to display countries colored by economic classification, with a legend that filters the map by category. Clicking a legend label dims all countries not in that category, while a base layer of water and country borders provides geographic context. The visualization is rendered as SVG using d3.geoPath and d3.geoNaturalEarth1 projection, with d3.scaleOrdinal for color and event handling for interactivity. It loads data from a World Bank CSV alongside TopoJSON country boundaries.