This example shows an interactive family tree using D3.js version 3. The visualization renders hierarchical data as a collapsible tree diagram, where clicking a node toggles its children. The code uses `d3.layout.tree` for layout, `d3.svg.diagonal` for curved links, and animated transitions via `transition()` with 750ms duration. Nodes are drawn as red-stroked circles with text labels, while links are green paths. The SVG output displays three generations of names, starting with Satyaveda as the root.