This example shows an interactive tree diagram mapping notable Wimbledon players, with each leaf node labeled by the number of championships won. The visualization uses D3.js version 3.5’s `d3.layout.tree` to compute hierarchical positions and `d3.svg.diagonal` for curved links. Nodes are rendered as SVG circles with text labels, and clicking a node triggers a 900-millisecond transition, collapsing or expanding its children. The page is built with a plain HTML file and embedded JavaScript, styled with simple CSS rules.