A smiling face is constructed from SVG circles, rendered in yellow with a red outline and featuring two eyes. The left eye is unfilled, while the right eye is filled with green, creating a simple, colorful character. Built with React, the code uses `ReactDOM.render` to inject the SVG into the page, with circle positions and dimensions set via `cx`, `cy`, and `r` attributes. The visualization relies on the `react` and `react-dom` libraries, with all shapes defined directly in the JavaScript source.