This example demonstrates a minimal D3.js starter setup, showing two circles (one red, one blue) connected by a path that updates dynamically. It uses an SVG rendering approach with D3 v7, where a line generator (`d3.line`) connects the circle coordinates. A `d3.timer` drives an update function that continuously re-reads the circles' positions and redraws the connecting line. The code also utilizes data binding with `selection.data()` and `selection.join()` to manage the path element between frames.