A pie chart displays revenue distribution across six product categories from a sample sales dataset, including Electronics, Home Appliances, Clothing, Books, Beauty Products, and Sports. The SVG rendering uses D3.js v7 functions such as `d3.rollup` for aggregation, `d3.pie` for layout, and `d3.arc` for slice generation, with each slice labeled by its revenue value and a separate legend built from the color scale.