# Inside the PageRank Algorithm

Delving into the inner-workings of Google PageRank algorithm and how it affects results.

## What Is PageRank?

PageRank is the algorithm used by the Google search engine, originally formulated by Sergey Brin and Larry Page in their paper "The Anatomy of a Large-Scale Hypertextual Web Search Engine.â

It is based on the premise, prevalent in the world of academia, that the importance of a research paper can be judged by the number of citations the paper has from other research papers. Brin and Page have simply transferred this premise to its web equivalent: the importance of a web page can be judged by the number of hyperlinks pointing to it from other web pages.

## So What Is the Algorithm?

It may look daunting to nonmathematicians, but the PageRank algorithm is in fact elegantly simple and is calculated as follows:

EquationÂ 8-0.Â

where:

• PR(A) is the PageRank of a page A.

• PR(T1) is the PageRank of a page T1.

• C(T1) is the number of outgoing links from the page T1.

• d is a damping factor in the range 0 < d < 1, usually set to 0.85.

The PageRank of a web page is therefore calculated as a sum of the PageRanks of all pages linking to it (its incoming links), divided by the number of links on each of those pages (its outgoing links).

## And What Does This Mean?

From a search engine marketerâs point of view, this means there are two ways in which PageRank can affect the position ...

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