A smiley face rendered as an SVG animation demonstrates core D3.js DOM manipulation. The code appends geometric elements—circles for the face and eyes, rectangles for eyebrows, and a path built with `d3.arc` for the mouth—onto an SVG canvas. Chained `transition().duration()` calls animate the eyebrow group’s vertical position, moving them up and down over four seconds. Using `d3.select` to create and transform elements, this example highlights how D3 binds data-independent shapes and drives simple timeline-based motion without external data sources.