http://www.campaignlive.co.uk/article/programmatic-advertising-key-terms-acronyms-explained/1356716
There are various programmatic models, here are four of the most common:
- Preferred deal: A non-auction model with a fixed CPM and non-guaranteed inventory.
- Programmatic guaranteed/direct: A non-auction model with a fixed CPM and guaranteed inventory.
- Private marketplace/exchange: An auction model that uses real-time bidding and price floors. It is open to an invitation-only group of buyers.
- Open exchange buy: An auction model based on real-time bidding and variable CPM. It is open to any buyer.