This map of California zip codes visualizes stroke mortality data from a CSV file, with each zip code area represented as a selectable polygon. The visualization uses a Mercator projection and D3’s geoPath to render the GeoJSON boundaries, while a zip code identifier appears as a tooltip when hovering over each region. Built with d3.v5, the map supports zooming and panning via d3.zoom, and employs event listeners to handle user interactions. The stroke counts are not visually encoded by color, but the data is accessible through the interactive tooltip.