PageRank

PageRank (PR) is a numeric rank assigned to a specific web page by Google that falls somewhere between 0 (lowest-relevance) and 10 (highest-relevance).

Page Rank, PageRank, PR

PageRank is based upon a large number of proprietary factors that come from complex mathematical modeling of what Google thinks will produce high quality SERPs. PageRank is, also, a trademark of Google.

Many SEOs try to split hairs over the real pagerank used by Google versus the pagerank that has been publicly released by Google. Drawing such a distinction is a total waste of time for all practical purposes.

The importance of a high pagerank in placing well in the SERPs is generally over valued by most people.  Page rank does not affect your placement in the SERPs as much as good Search Engine Optimization (SEO) does.