This example uses a hierarchical dataset of world regions and countries to render a vertical tree diagram. The visualization displays the structure of continents, subregions, and nations as linked nodes using D3’s `tree` layout and `hierarchy` function. SVG paths connect parent and child elements with curved, vertical links generated by `linkVertical`, while the JSON data is loaded asynchronously via `json`. The chart adapts its dimensions to the browser window, with no interactive behavior beyond the static layout.