Question: what is pr6 in search engine optimisation? or any pr1 ,2 also.

Answer: PR6 (or PR0 to PR10) refers to the PageRank Display on the Google Toolbar http://www.google.com/support/toolbar/bin/static.py?page=features.html&hl=en and according to Google tells you "... how Google's algorithms assess the importance of the page you're viewing".\n\nProfessional SEOs refer to it as Toolbar PR or TPR to differentiate it from the PageRank formulated by Google's Brin and Page in this paper http://www-db.stanford.edu/~backrub/google.html which can have non integer values outside the range 0-10.\n\nThe relationship between PR and TPR is assumed to be logarithmic but outside of a few engineers in Google no one knows the exact relationship or even if there is any direct relationship at all. \n\nBecause PageRank is keyword independent the search engine results pages are not in TPR order and pages with a lower TPR will often rank higher than pages with a higher TPR for any given search term.\n\nBecause of those things and the fact that TPR is only updated every 3 months or so it is only of interest to the lower echelons of the SEO community and completely disregarded by the professional SEOs.\n\nI advise you to disregard it as well and concentrate or more important metrics.
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