This example visualizes a social network as an interactive force-directed graph using D3.js. The SVG renders circular nodes labeled with person names and blue directed links with arrowheads, showing friendship connections weighted by a numeric value. The layout relies on `d3.forceSimulation` with `forceLink`, `forceManyBody`, `forceCollide`, and `forceCenter` to position the nodes. Nodes are draggable via `d3.drag`, and hovering highlights a node by adding a CSS class. Data comes from the local `graph.json` file.