An interactive tree diagram maps the hierarchy of Muscle Cars, from Ford and Dodge down to models like Mustang, Charger, and SRT. The visualization loads hierarchical data from a JSON file and renders it as colored, animated SVG nodes with connecting links and tooltips. Built with D3.js v3, the example uses `d3.layout.tree`, `d3.behavior.zoom`, and SVG elements to support click-to-collapse behavior and drag-to-pan navigation.