This network graph visualizes hierarchical relationships between main nodes, child nodes, and leaf nodes using a force-directed layout. The d3.forceSimulation API with forceManyBody, forceLink, and forceCenter forces positions nodes and links, while SVG circles and lines render the graph. Node size encodes hierarchy level, and colors distinguish four main site clusters. Users can drag circles to reposition nodes, with drag interaction restarting the simulation. The data.js file programmatically defines nodes and links, including parent-child connections and inter-site links.