A smiley face built from SVG circles and rectangles in red on a blank canvas demonstrates basic DOM manipulation and animation with D3.js. The eyebrows shift upward over one second, then return to their original position over eight seconds using chained transitions. The code constructs elements by appending to groups, calculates positions from window dimensions, and leverages D3’s `select`, `append`, `attr`, and `transition().duration()` APIs, with a custom triangle symbol added via `d3.symbol()`.