The priority given to the placement of a link on the results page of a Web search. For example, Google's PageRank system, named after co-founder Larry Page, classifies a site based on the number of links that point to it from other sites (the "backlinks"). The concept is that if very prominent sites link to a site, the site has greater value. The more popular the backlink sites themselves are, the higher the ranking as well.
In addition to Google's PageRank, the content and organization of the pages on the site are criteria used in the page ranking algorithm. Google claims its algorithm uses more than 200 factors to determine the value of a page. The amount of buzz on social media also plays an important part.
The Algorithm Changes
Because countless websites are laden with unnecessary content in order to boost their ranking, the search engine formulas are often changed to prevent deceptive content from achieving permanent high ranks. See link juice
, search engine optimization
, Google bomb
and social bookmarking site
Page Ranking Technology
Although the Web page ranked #3 may have a lot more useful information than the one ranked #1, search engine software cannot really tell which is the superior website from a quality perspective. It can only know which ones are popular, and link swaps (you link to me - I link to you) are created to do nothing more than make pages popular.