Difference Between Internal Page Rank or External Page rank ?

This is Not new but New to so many SEO that what is that Internal Page RAnk And External Page RAnk...well i m also in a lil confusion 2.... that what actually is Internal And External PR..... There Bar showing us static PR is called External PR... And the google calculating PR that Constantly fluctuating by the min or hr is called Internal PR.....

Internal PR is a complex of formulae and algorithms which is only known to Google. External PR is only an indicative figure displayed on the toolbar which has very little or no significance in relation to actual PR.

I read Article on that .... IT is like that....

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Internal Page Rank vs. External Page Rank
Most web masters consider Page Rank to be the 1-10 green bar ranking in Google’s Toolbar. In actuality, this is 10,000 foot view of what’s really going on behind the scenes. It’s like looking at earth from space and saying, “Earth consists of water, clouds and land”. Yes, earth does consist of those things, but there’s a lot more to earth than just that.

For clairfication purposes, we’ll call the 1-10 toolbar score, “External Page Rank” and we’ll refer to the behind-the-scenes score that Google uses in it’s algorithm the “Internal Page Rank”.

So here is the main break-down…

1. External Page Rank is for consumers and does not affect rankings.
2. External Page Rank is on a scale of 1-10. (Example: PR 5)
3. External Page Rank gets updated every few months.

1. Internal Page Rank is for Google and is factored into rankings.
2. Internal Page Rank has a much detailed range. (Example: PR 5.38409)
3. Internal Page Rank is constantly updated.

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