This example demonstrates a force-directed node-link diagram of a social network, using data from Dublin infection contact traces. The visualization shows 410 nodes and their connections, with node colors representing group assignments based on link counts. Implemented with d3.forceSimulation, d3.forceLink, and d3.forceManyBody, it computes the layout. Users can drag nodes and zoom the SVG canvas using d3.zoom. Node and link positions update on each simulation tick, and the graph is rendered as SVG circles and lines.