Page Rank, normally known as “PR” is a numeric value that represents the importance of the webpage on the web. Page Rank is one the factors to calculate rank of the website in different SERP for specific keywords as there are many other factors also which are equally contributed in the calculation of ranking. PageRank is Google's way of deciding a page's importance. The highest the PR for the webpage, the better it will be. Google gives the PR out of 10.
Now in the process of calculating PR, Google gives highest weight age to the "LINKS". Google figures that when one page links to another page, it is effectively casting a vote for the other page. The maximum votes the page has, maximum will be the chances for the page rank because it is assumed that, maximum the votes, important the page must be.
But the links or votes should be quality links. Google normally identify bad links (Link farms, FFA, theme less pages etc.) and gives no importance to them. So its good to have quality links for your site.
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