[sullivandanny]

The title is about "Google PageRank score," not Google PageRank.

PageRank was one part of the reason we have a search as powerful as Google, the use of links to assign an authority score. Another big part was the use of link context -- which isn't part of PageRank but part of the overall search algorithm at Google.

PageRank score is when Google revealed those scores to the public for any page. That's not something it had to do, in order to use PageRank as part of it algorithm. But in doing so, it fueled an explosion in link spam.