This example shows a hierarchical tree of car types, branching into transmission categories (Automatic, Manual, Semi-Automatic) and then door counts, with nodes rendered as distinct shapes (rectangles, circles, rotated squares) and colored per depth level. It uses d3.csv to load a remote dataset, then processes the data into a nested structure before applying d3.tree and d3.hierarchy to compute the layout. The visualization renders as SVG, drawing curved links via d3.linkHorizontal and positioning nodes with explicit translate transforms, while each node’s shape and fill color are assigned conditionally based on its depth.