Can you maybe elaborate on what is unclear? The user types are explained in this link. Your Qlik site license will have one or more Professional Licenses and possibly some Analyzer licenses as well. Those two tabs show you which users have Analyzer and Professional licenses assigned to them. You can use those two tabs to assign licenses to users or you can assign the licenses dynamically based on a set of rules (that you need to set up if you want to do this - look at Dynamic access assignment in the link above).