Google Ad Manager is an ad serving platform that helps make your ad management easier by bringing all your traffic needs in one place. By linking your Ad Manager account to Analytics, you get a mixed view of advertising revenue and user behavior to improve your earnings strategy.
Publishers use Ad Manager to display advertisements. Also, use Google Analytics to understand user behavior. No system has significant information about the relationship between these two areas - how user behavior affects revenue and how advertising affects user behavior. Ad Manager publishers can view reporting linked together between Ad Manager and Google Analytics 360 in the Google Analytics UI from Ad Manager Reporting Integration. This is a mixed report that shows Ad Manager impressions/clicks/revenue, separated from the source of traffic or a particular page.
Google AdSense shows publishers how to make money from their online content. AdSense works by matching ads to your site based on your content and people visiting the website. People who want to advertise their products, make these advertisements, and pay for them. These advertisers pay different prices for different advertisements, so there will be a difference in your earnings from them.