PageRank is a link analysis algorithm that is part of the Google search algorithm.
The name PageRank is trademarked by Google and the PageRank algorithm is patented by Stanford University, not by Google (go figure), but Google has exclusive license rights to the algorithm.
The PageRank algorithm assigns a numerical value to each link and by aggregating them in some way the PageRank algorithm is an integral and important part of the overall Google search algorithm.
This article is part of a series about local SEO marketing. For access to all the articles in the series, click on the link in the prior sentence.
How does it matter to you? Simply put, you want to attract back links from web sites that have a higher Page Rank value. That values range from 1 to 10, 10 being highest.
Although the details of PageRank on a link by link basis are not useful to local SEO marketing, it is easy to determine the Page Rank value of any website. There are many free and commercial tools that make this easy.
When looking for relationships to nurture that are likely to result in back links to your websites, consider the PageRank value of the websites in question. Higher PageRank values provides more valuable back links.
You will find much more information about local SEO marketing by reading the entire series of articles.