To further confuse you that's not because of the name PageRank. That comes from the inventor Larry Page
But engines rank documents or pages, not entire sites
However looking at the concept of trusted domains - domains with lots of well ranled pages - it's worth getting a link from one of their lower ranked pages as these pages may well experience an increase in their rank because of where they are - on a trusted domain.
When securing a link as yourself this. If I was Google would I value the 'opinion' of the page doing the linking?
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