This example visualizes the Zachary Karate Club network, a social graph of 34 members, using a force-directed node-link diagram. Nodes represent individuals and links represent friendships, with interactive features allowing users to hover over nodes to view IDs and neighbors, or drag nodes to reposition them. The visualization is built with D3 v7, using `d3.forceSimulation` for physics-based layout, `d3.forceLink` and `d3.forceManyBody` for forces, and `d3.drag` for node interaction. Data comes from a CSV file loaded via `d3.csv`, with edges and nodes rendered as SVG lines and circles.