PageRank is a term used to establish the level of popularity of a website and one of the aspects taken into consideration to establish the position of the website on the search engines.
The more a website is linked from the pages of other websites, the higher its ‘vote’.
For the interpretation and the definition of the popularity of a website, apart from the number of visits, what is also taken into consideration is the relevance of the content of the web pages which make up the website and of those connected to it, based on the terms and the criteria  used to reach it through the search engines. This is carried out to guarantee the validity of the search results.
A website with a good PageRank score is usually visited more frequently by the search engine spiders, which will first take into consideration possible updates of the pages.