Hi.
With Power BI Premium, you can publish a Paginated Report to a Premium Workspace and then give access to anyone with only a Free Licence. (Microsoft call this "Unlimited Distribution" in the licence documents).
With Power BI Premium Per User (PPU), a user with a PPU licence can publish a Paginated Report to a PPU Workspace and share it with other PPU licence holders only.
It's a numbers thing, if you only have a few users that need to view the report it may be cheaper to buy them all PPU licences (PPU is an individual licence per head). Of you have many users (more than 200) that need to view the Report it may be more cost effective to invest in a Premium licence for the organisation (Premium is licenced by Capacity not user).
If you have a Premium licence, it is unlikely you'll need PPU licences, you can use a Pro licence to create the reports and publish them to a Premium Workspace. If you don't have a Premium licence you'll need PPU licences for everyone who wants to view and interact with the report. There's only a few technical scenarios where you'll need both PPU and Premium.
Hope this helps
Stuart
