PageRank is a link analysis algorithm originally developed by Google to estimate how important a web page is based on links. The basic idea is that a link from one page to another can act like a “vote,” and votes from well linked, reputable pages tend to carry more weight. In classic explanations, PageRank is often described as the probability that a random web surfer would land on a page by following links, which helps explain why links are such a foundational signal in search.
In modern SEO, it is best to treat PageRank as one part of a much larger ranking system rather than a single score that determines everything. Links can still help distribute authority across the web and within your site, but what matters most is earning relevant, editorial links that make sense to users and support accurate, trustworthy content. Clear internal linking also helps, since it guides both visitors and crawlers to your most important pages and reduces ambiguity about which pages you consider key.