Bill Slawski explains it this way:
If a link is in the main content area of a page, uses a font and color that make it stand out, and has text that makes people want to click on it, it can pass a good amount of PageRank. On the other hand, if it combines characteristics that make it less likely to be clicked on—for example, if it's in the footer of the page, the same color as the rest of the text on the page, the same font, and uses anchor text that people don't care about—it may not pass much PageRank.
— Bill Slawski
Contextual links, those placed within the body of a web page's content, and not in the footer or sidebar for example, are generally higher quality links, and are essential elements of a good strategy.
Not all links pass PageRank, and not all links impact a site's rankings.
Links can have different attributes applied to them. The argentina phone number data main ones to know are: nofollow, sponsored, and UGC.
Links that have a rel="nofollow" attribute indicate that Google should not crawl them and that the two sites should not be associated from a ranking perspective.
Rel="sponsored" attributes indicate that the link was paid for (and therefore PageRank should not be passed).