CPM
full spelling ： Cost Per Mille
Cost per Mille is a commonly used measurement in advertising. In Latin mille means thousand, therefore, CPM means cost per thousand.
The advertiser is billed based on the number of times an advertisement is seen by a consumer, regardless of the consumer's subsequent action. For example, in online advertising, if a website sells banner ads for a $30 CPM, that means it costs $30 to show the banner on 1000 page views. Most graphical online advertising and nearly all radio, television, newspaper and magazine advertising, is sold on some kind of CPM basis.