An algorithm is an operational programming method. Algorithms are used by search engines to intelligently index content and display search results. In laymen’s terms, an algorithm is an operational programming rule that determines how a search engine indexes content and displays the results to its users. Search engines have an algorithm (a set of rules/codes) that determine how your website is ranked. Your website could come up # 7 or # 777,000 depending on how well you or your SEO consultant understand these terms.