CPM is a type of online advertising that has nothing to do with the actions that users take on publisher sites. The term CPM stands for cost-per-thousand. C stands for charge, P stands by and M stands for thousand as in the Roman numeral value of M is 1000.
What thousand abbreviations in this formula? Thousand is a banner impression. So if you are an advertiser who prefer to buy ad using CPM then you will have to pay for every thousand times your ad on the publisher indicates its website. You can also read more here to get more information about CPM advertising.
This method is advantageous for both publishers and advertisers, but may be more profitable for the publisher because he gets paid for each thousand page views his sites receive.
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This method is also independent of the actions of users on the publisher's site because if the visitor has been to the site publishers display ads then this will be counted as a page view, and productive from the publisher will increase.
This means that if a visitor visits the site of the issuer does not click on the ad then also publishers will be paid. So in this way is more profitable CPM for each publisher receives a high page views on its website.
This method may or may not help the owner of advertisement for the advertiser will be paid only if a visitor saw the ad also clicks on the ad and buy something on his site.
So the ad owner can benefit from this method only if his sites receive higher click URL from the publisher site and the site itself also has a high conversion ratio.