A Smiley Face is a simple SVG rendering of a classic smiley face, with a yellow circle, two black eyes, and a curved mouth. Built with React and D3 v7, the example uses D3’s `arc()` generator to compute the mouth path, while positions and radii for the face and features are defined via constants. The SVG is centered within a 960×500 viewport, and all shapes are drawn using React JSX elements within a `<g>` transform group.