This example presents a force-directed graph visualizing a social network of named individuals. The graph uses nodes and weighted links to show connections, with each person’s name displayed beside a colored circle. The visualization is built using D3 version 2’s `d3.layout.force()` API to simulate the physics of repulsion and attraction. The code loads node and link data from an external `graph.json` file, renders the network as SVG, and includes interactive dragging of nodes via `force.drag`. Node fill colors reflect per-node values from the dataset.