A D3.js pie chart displays the proportional values of twenty product categories, with each slice labeled directly on the chart. A legend on the right side maps category names to their corresponding colors. The visualization uses `d3.pie()` to compute arc data, `d3.arc()` to generate path and label geometry, and `d3.scaleOrdinal(d3.schemeCategory10)` for categorical coloring. The SVG is rendered at 800x600 pixels, with the pie centered on the left half of the canvas.