Can you please explain the difference between Audience overview and Visitors overview?
The difference between the Audience overview and Visitors overview is that they show different stats.
Audience overview shows what is viewed (stats about your website) and Visitors overview shows who views the website (stats about website visitors).
P.S. Google Analytics does not collect data if the user is logged in in his / her website. That is, the page views made by website administrator will not be counted.