PageRank

Google’s PageRank was named after one of their founders Larry Page. It was a link analysis algorithm that assigned a numerical value of 0-10 to denote importance or authority of a webpage. On April 15, 2016 Google turned off the display that showed PageRank data of their toolbar. While it still uses PageRank to determine rankings in search results it is no longer visible to site owners as is not considered an important metric to track.

Page Authority (PA) is often confused with PageRank but should not be used synonymously. Page Authority is a number between 1-100 that Moz uses to denote the quality of a page based on their own proprietary algorithm.