This world map visualizes population values for 20 countries using a sequential blue color scale, with lighter shades for smaller populations and darker shades for larger ones. Hovering over a country displays a tooltip with its name and population. The visualization uses d3.geoNaturalEarth1 for projection, d3.geoPath for rendering SVG paths from TopoJSON data, and d3.scaleSequential with d3.interpolateBlues for coloring. Population data comes from a local CSV file, while country boundaries load from the world-atlas TopoJSON collection.