Page Rank
The Google PageRank is an algorithm that measures the popularity of a linked document, e.g. a web site, based on the number and quality of links (e.g. natural links) that point to it. The basic idea is the simulation of a human surfer to determine the realistic likeliness of a site being hit.
The PageRank is an important factor for the ranking of a web site. Originally invented by the founders of Google, other search engines copied the concept in the meanwhile, e.g. in form of Bing's Page Score.
