A smiling face is rendered as an SVG using React components for the background circle, eyes, and mouth. The face is composed of simple geometric shapes, with the mouth drawn using a D3 arc generator. The example demonstrates a static composition, with no interactive mouse events implemented despite the title. The code uses React to structure the SVG elements and D3's `arc()` function to define the mouth path, with a fixed viewport size of 960 by 500 pixels.