This example visualizes a small social network of eight people and their friendship connections. Users can drag nodes around, with hover effects highlighting nodes in red. The graph uses D3 version 6’s `d3.forceSimulation` with force-link, force-many-body, force-collide, and force-center to position nodes and links, rendered as SVG circles and lines. Data comes from a local `data.json` file, and the code implements drag behavior and marker arrowheads for the directed edges.