SALSA and PageRank are algorithms that analyze the link structure of web pages to determine authoritative pages. SALSA models the web as two interacting Markov chains, with one for hubs (pages that link to many others) and one for authorities (pages that many point to). It computes hub and authority scores for pages through these chains. PageRank also models the web as a graph, and computes page importance through a recursive equation based on the concept of a random web surfer following links. Both leverage the concept of a random walk on the link graph to determine important pages.