PageRank (Google)

PageRank is the name of one of the first, and most well-known, algorithms used by Google to determine the importance of a web page.

It is based on the thesis that more important pages are more likely to receive backlinks from other pages, which is a kind of merit rating for that site. It assigns a numerical weight to each element of a set of linked documents in order to quantify the relative importance of each document within the set. Not all votes carry the same weight: the most popular web pages express higher value votes through their links; however, the popularity of a site is determined not only by the quantity and quality of links, but also by such elements as the relevance of a page’s content, related pages, and search terms, as well as the spread and popularity of the topic covered on the site.

Over time, the expression PageRank has also come to mean the most relevant pages or sites in relation to the terms searched. The technique of defining and optimizing PageRank toward the pages of a site is called PageRank Sculpting.

Originally, Page Rank was the main ranking factor in Google search results, but now it is only one of many signals Google uses to rank pages.