An animated smiley face rendered in SVG demonstrates core DOM manipulation with D3.js v5. The face, built from circles, rectangles, and a path, features eyebrows that animate by chaining `transition().duration()` calls to shift their vertical position over time. The code constructs the facial features using D3’s `select` and `append` methods, with the mouth drawn via the `arc` function to generate a curved path. The example highlights basic D3 transitions and coordinate transformations within a fixed 960×500 SVG canvas.