This animated visualization shows a rotating pentagon constructed from a central point to five outer vertices, with its size cycling continuously between expanding and contracting. The code generates 50 spokes and connecting wheel lines using D3 v4’s selection and data-join methods, computing point positions with trigonometric functions. A `setInterval` loop triggers a re-render every 10 milliseconds, incrementing the rotation angle and adjusting the radius length, while an `if` statement reverses the growth direction when the length exceeds 300 pixels or drops below zero. All rendering is done via SVG line elements, cleared and redrawn on each frame.