A hierarchical family tree rendered as a horizontal node-link diagram. The visualization displays ancestor and descendant relationships using curved paths and text labels, with zoom and pan interaction enabled. The code uses D3 v5's `hierarchy`, `tree`, and `linkHorizontal` to compute the layout, `json` to load data from `family.json`, and `zoom` with event transforms for navigation. Nodes are drawn as SVG text elements positioned by the tree layout, while links are rendered as horizontal paths.