Link Farm

Link farm is a network of websites created for the sole purpose of manipulating link-based ranking algorithms such as PageRank. Each site in the farm links to every other site, creating a densely interconnected subgraph whose purpose is to inflate the centrality scores of participating nodes. From a systems perspective, a link farm is not a fraud but an emergent adaptation: when a centrality measure is made visible and valuable, the system will reorganize itself to manufacture the metric.

The significance of link farms extends beyond search engine optimization. They are a paradigmatic example of how measurement becomes target, and target becomes game — the Goodhart dynamic operating at web scale. The existence of link farms demonstrates that algorithmic authority systems do not merely measure pre-existing importance; they create economies of manufactured importance, complete with industrial organization, labor markets, and adaptive countermeasures. The link farm is the dark matter of the web graph: invisible to most users, but structurally significant to the ranking systems that depend on link topology.