Google Pagerank is the algorithm behind the natural occurring ranking of websites for various keyword searches. Pagerank is assessed by Google every 2 months or so and assigned to indexed websites from a low score of 0 to a high score of 10. Google is one of the few PR 10 websites.

Pagerank is determined a variety of ways. At the surface level, Google Pagerank is assigned based on the quality and quantity of hyperlinks inbound to your website. In other words, the website with the most links and the best links wins. The trick to Pagerank is understanding what a quality link is.

Google Pagerank has  been the cause of many banned SEO practices, specifically aggressive link spamming techniques that are now categorized as Black Hat SEO and frowned upon. Keyword matches in text links and URLs can help avoid being black-listed by Google.