A grid of eighteen smiley faces, each with randomized eye and mouth thickness, demonstrates reusable React components paired with D3. The `Face` component composes smaller pieces like `BackgroundCircle`, `Eyes`, and `Mouth`, with the latter using `d3.arc` to draw an arc path. The `FaceContainer` wraps everything in an SVG group translated to the face center. Rendered with React 17 and D3 v7, the example shows how declarative JSX and D3 shape generators can build modular data visualizations.