You get Page Rank (PR) by having backward links from other website pages that have a higher PR rating than your site page the link is to. The PR of your site is updated about once of month when Google updates their database of web pages.

         For example if you have a backward link from a site that has a PR of 5, some of that PR be will transferred from their website to your website page they linked to. These links are called back links sites with high Page Rank will get crawled by the search engine bots more often, and the crawls will be deeper.

         While Google takes into consideration the Page Rank of your site, high PR doesn't always equate to a higher Search Engine Results Position (SERP). You can have high PR and have a low SERP on a certain keyword phrase, while some other site can have low PR but have a high SERP on the same keyword phrase.

         In your pursue for a high PR keep in mind that numerous relevant keyword anchor text back links will get you a higher SERP than just raw high PR and that with numerous relevant keyword anchor text back links will come PR.

         You aim should not be just for high PR, but for proper back links that will bring with them a higher PR.