Backlinks are prized by many SEO practitioners because it is thought that by gaining more backlinks to a website, or webpage, the website or webpage will be seen as being more trustworthy or authoritative by search engines.
And in turn, the search engine would reward the website or webpage with a higher ranking on the search engine results pages.
This concept or idea that search engines value a website or webpage more because of the number of backlinks it has is formally known as PageRank, “Link equity,” or “Ranking credit”.