Page Rank by Livecustomer.com - Specifically, Google considers the quantity, quality and anchor text of back links when determining PageRank, whereas Yahoo and MSN rely heavily upon the quantity of a site’s back links when ranking pages. This is the primary difference between the main search engines. In essence, the search engine companies have determined the web community should vote upon popular and important websites by linking to them. Therefore, the quantity and quality of votes are important factors search engines consider when ranking websites.