This example draws a simple smiling face in an SVG canvas using D3.js v5. It shows how to compose basic shapes—a yellow circle for the head, black arcs for the eyes and mouth, and rectangles for the eyebrows—by chaining D3 selections and attribute setters. The code uses `d3.select` and `d3.arc` to generate the mouth path, with hardcoded coordinates and transformations for positioning.