This example renders a choropleth map of Massachusetts using the Albers equal-area conic projection. It displays the state’s geographic boundaries as SVG paths, colored with a teal stroke and fill. The visualization uses React to manage state and rendering, calling `d3.geoPath` with `d3.geoAlbers` to project the GeoJSON data fetched from a GitHub gist via `d3.json`. The `topojson` library’s `feature` function converts the TopoJSON structure into GeoJSON features for plotting.