A force-directed graph represents a network of application and host nodes. The visualization uses D3’s `forceSimulation` with `forceManyBody` and `forceLink` to arrange nodes, with larger main nodes connected by longer links and smaller leaf nodes clustered nearby. Node colors come from a predefined palette, and each node’s size determines its radius. Users can drag nodes, which sets fixed positions and restarts the simulation. The example is built with React and renders to SVG, using D3 v6.