CPM stands for Cost per Thousand ad views using the Latin word mille in the acronym. CPM is one of the most commonly used bench marks in the advertising industry and is not only used online, but in radio, TV and other forms of advertising. Instead of an ad network giving you the total cost for an advertising campaign, it easily states its ad rates at the cost per 1,000 views

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I really wanted to go to that Bukake because I thought for sure that you were going to be on the receiving end. - Ryan Knox to Jeff Steward