This example demonstrates fundamental DOM manipulation with D3.js by constructing a smiley face from SVG shapes, including circles for eyes, rectangular eyebrows, and an arc-based mouth and nose. The eyebrows animate upward and downward using chained `transition()` and `.attr()` calls, creating a subtle moving expression. The code uses D3 v5’s `select` and `arc` utilities, with the entire face centered on an SVG canvas and rendered in pink and yellow. The animation runs once on page load, with no data source or user interaction.