Also known as cost-per-impression or CPM for cost-per-mille (mille is the Latin word for thousand), cost-per-thousand is an advertising revenue system used by search engines and ad networks in which advertising companies pay an agreed amount for every 1,000 users who see their ads, regardless of whether a click-through or conversion is achieved. CPM is typically used for Banner Ad sales, while Cost-Per-Click is typically used for text link advertising.