This example shows a collection of four smiling-face SVGs rendered side by side in different sizes, each built from nested circles. It demonstrates how React components can encapsulate SVG drawing logic, with a `FaceContainer` component defining face, eye position, and radius values based on width and height props. The code uses React and ReactDOM to render the components into the DOM, producing static yellow faces with grey eyes. No interaction or animation is present; the visualization simply displays the geometric output of the component using SVG circle elements.