CPM or Cost Per Impression

Cost Per Impression is a phrase often used in online advertising and marketing related to web traffic. It is used for measuring the worth and cost of a specific e-marketing campaign.

This technique is applied with web banners, text links, e-mail spam, and opt-in e-mail advertising, although opt-in e-mail advertising is more commonly charged on a Cost Per Action (CPA) basis. The Cost Per Impression is often measured using the CPM (Cost Per Mille) metric. (A CPM is the cost of one thousand (1,000) impressions.) CPM is considered the optimal form of selling online advertising from the publisher's point of view. A publisher gets paid for each ad that is shown.

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