This example displays a choropleth map of India using a Mercator projection, with each state filled by a categorical color scale. The visualization is rendered as SVG paths generated through d3.geoPath, with hover interactions changing state colors to green. The code loads TopoJSON data from a GitHub gist, parses it using the topojson feature function, and applies d3.scaleOrdinal with schemeCategory10 for coloring. The map is built with React and D3 v5, featuring zoom support and a title header.