This example shows a small social network graph with nine people (including Shashank, Anju, and Prem) and eight weighted connections. The d3.v4 code uses `d3.layout.force` to position the nodes, with links drawn as black lines whose stroke width reflects the connection weight, and nodes represented as blue circles with red text labels. The SVG renders the graph at 900 by 600 pixels, and the nodes are draggable via `force.drag`, with positions updating on each tick event. Graph data comes from the local `graph.json` file.