This choropleth map visualizes global population density, with each country colored on a blue sequential scale, from light shades for lower values to darker blues for higher densities. Countries without data appear in gray. The visualization uses D3.js v7 to load TopoJSON world map data and a CSV file, converting them to GeoJSON features. The map is rendered as SVG paths using a Natural Earth projection, with an interactive tooltip on hover and a linear gradient legend showing the density range.