This example shows how to build a simple smiley face with D3.js, using SVG circles to represent facial features and animated eyebrows that move in response to a timer. The code demonstrates fundamental DOM manipulation by selecting the SVG element, appending circles with positional and styling attributes, and using D3's selection methods to update the eyebrow positions over time. The face is drawn with a yellow circle for the head and additional circles or paths for eyes, eyebrows, and a mouth, all rendered in a 960×500 viewport.