This example shows a force-directed network graph of countries, with nodes representing nations and links indicating connections between them. The visualization uses the D3.js v4 library, specifically the `d3.layout.force` API, to simulate physical forces that position the nodes and links within an SVG canvas. Node labels display country names, and link stroke widths reflect the numeric `weight` values from the JSON data file, with thicker lines for stronger connections. The graph loads data from `graphFile.json` and supports interactive dragging of nodes via `force.drag`.