Search engines use a variety of algorithms to determine relevancy ranking. Some of these include determining whether the search term appears in the body text or URL of a web page. Many search engines check for instances will remove suspect pages from their indexes. Also, people working for a search-engine organization can quickly block the results-listing from entire websites that use, perhaps alerted by user complaints of false matches. The rise made of the leading search engines of the time less useful. Using sinister methods to have websites rank higher in search engine results is commonly referred to in the
SEO industry as Black Hat
SEO.