One of the most popular forms of exercise among many search engine optimizers—both the third-party firms that do it for others and the advertisers who spiff up their own Web pages for better natural search rankings—is a periodic workout called “chasing the algorithm”. The race begins when Google or Yahoo! updates some portion of the software that determines how they look at Web pages and decide which are most relevant and valuable to a searcher. The engine makes that change; Web operators see their rankings rise or fall as a result; and they, or their outside search engine optimization (SEO) firm, scramble to get back the old rank by providing the new elements the search engine now needs. After a few months, the engines make another change, and it’s off to the races again.