This example visualizes global population data by plotting cities as semi-transparent circles on a Natural Earth projected world map. A square-root scale maps each city’s population to circle radius, with the largest cities appearing most prominent. The visualization uses React for component structure and D3 v5 APIs including `geoNaturalEarth1`, `geoPath`, `geoGraticule`, and `scaleSqrt`. Country boundaries and graticules come from the World Atlas TopoJSON, while city coordinates and populations are loaded from a clean CSV dataset.