This bubble diagram sample shows the websites interlinking to illustrate PageRank concept. It was redesigned from the Wikimedia Commons file: Websites interlinking to illustrate PageRank.png.
"Suppose each circle is a website, and an arrow is a link from one website to another, such that a user can click on a link within, say, website F to go to website B, but not vice versa. Google crawlers examine which websites link to each other and assume that websites with more incoming links are what users want."
This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication. [creativecommons.org/publicdomain/zero/1.0/deed.en]
"PageRank is an algorithm used by Google Search to rank websites in their search engine results. PageRank was named after Larry Page, one of the founders of Google. PageRank is a way of measuring the importance of website pages. ...
It is not the only algorithm used by Google to order search engine results, but it is the first algorithm that was used by the company, and it is the best-known. Google uses an automated web spider called Googlebot to actually count links and gather other information on web pages." [PageRank. Wikipedia]
The bubble diagram example "PageRank" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Bubble Diagrams solution from the area "What is a Diagram" of ConceptDraw Solution Park.