A smiling face built from SVG shapes demonstrates D3’s arc generator and chained transition methods. The code draws a yellow circle for the face, two arc paths for closed, winking eyes, and a lower arc for the mouth, all centered within a 960×500 viewport. Using d3.arc with explicit inner and outer radii and start/end angles, the example shows how to construct curved paths without external data. The React starter wraps D3 v5 selections, while commented-out code hints at possible animated eye transitions via .transition().duration().