At the end of an iteration, the team shows the working product to the product owner. Yes, that’s a demo. The idea behind agile is that you inspect and adapt (Agile Project Management with Scrum [Sch04]) as you proceed. That’s why you need to demo the product to your product owner.
In addition, the team discusses the velocity charts and anything else the team creates as part of their project dashboard. Finally, the team holds an interim retrospective to learn from what happened during this iteration.
If you use agile approaches, you can shortcut all the meetings and manage with just the release planning, daily standups, retrospectives, and iteration reviews.