A smiling face is drawn as a yellow circle with a black stroke, two eyes, and a curved mouth. The face is centered within a 960 by 500 SVG canvas. The code uses React to assemble the face from components like `BackgroundCircle`, `Eyes`, and `Mouth`, while D3’s `arc` function generates the mouth path. The `Face` component receives specific numeric values for dimensions and positioning, such as `centerX`, `centerY`, and `eyeOffsetX`.