PageRank is an Algorithm that Google Search Engine do the ranking of websites. The term PageRank was named after Larry Page (Google's co-founder). PageRank is a way of measuring the importance of website pages.
Google explains that PageRank works by counting the number and quality of links to a page to determine a rough estimate of how important the website is. The underlying assumption is that more important websites are likely to receive more links from other websites.
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 most well-known. Google uses an automated web spider called Googlebot to actually count links and gather other information on web pages.
In an attempt to “cheat the system”, some website owners have tried to purchase links back to their website hoping for a higher Page Rank. However, those low quality links can have a negative impact and result in a lower Google Page Rank. In addition, a website may be penalized or blocked from search results, giving priority to websites and web pages that have quality backlinks and content that is valuable to humans. If your Page Rank Test results are lower than you’d like them to be, you might want to use this Back Link Check tool to determine the Page Rank (value) of sites that are linking to your website or page, then further examine the value of each individual link with this Link Analysis tool. Also, you can use this Backlink Maker tool to create valuable (high PR) backlinks. Page Rank is only updated 2 to 3 times a year, so the best policy is to put your best foot forward with value link building and quality content, and then run this test on a quarterly basis to see if there are any changes