Cost per Mille (CPM) – A common way to charge for digital marketing, especially when it comes to banners or brand advertising. You agree to pay a certain price per 1,000 (mille means thousand) impressions your ad receives. SEM can also use CPM as a payment model for contextual advertising. CPM can sometimes feel a bit abstract as an abbreviation and should perhaps be called Cost per 1,000 Impressions.