A smiling face is drawn as a yellow SVG circle with black stroke, two black eyes, and a curved mouth. The face is assembled from React components, with the head, eyes, and mouth positioned relative to a center point. The mouth uses d3.arc to create a half-circle path, while the face container translates the SVG group to center the drawing. All parameters, such as eye offset and mouth radius, are passed as props to control the face’s proportions.