A Sankey diagram of car evaluation data visualizes the flow of car attributes—buying price, maintenance cost, doors, persons, luggage boot, and safety—toward an acceptability outcome. The diagram renders nodes and curved links as SVG elements using D3.js v5, with the custom `d3.sankey` layout computing node positions and link widths. Draggable nodes allow interactive repositioning, triggering a relayout that updates link paths via `d3.sankeyLinkHorizontal`. Data is loaded from a CSV text file using `d3.csvParse`.