This visualization displays the hierarchical structure of world countries, organized by continent and subregion, as an interactive tree diagram. It uses D3 v5’s `tree` layout, `linkHorizontal` generator, and `zoom` behavior on an SVG canvas, with nodes labeled by country names. The data is loaded from a JSON file, and the static layout supports pan and zoom via D3’s zoom event. Text size decreases with node depth to emphasize hierarchy.