This example shows a simple smiley face constructed from a yellow circle with a black outline, two dark eye circles, and a mouth drawn as an arc. The face is built using React components that render SVG elements, with D3's `arc` function generating the mouth’s path. The `arc` is configured with inner and outer radii plus start and end angles. All shapes are positioned relative to a central group transform, which is translated to the middle of a 960-by-500 viewport.