Cost-Per-Acquisition Advertising (CPA advertising) - also known as Cost-Per-Action advertising - is an online advertising process in which an advertiser only pays per conversion, whether it be a lead or a sale.
CPA advertising differs greatly from traditional forms of online advertising such as the Cost-Per-Impression (CPM) or Cost-Per-Click (CPC) models. It is strictly performance based advertising; instead of the advertiser having to pay the publisher for every ad impression or for every click-through to a website and hoping for a conversion to a lead or a sale, the advertiser gets the traffic for free and only pays for the results.
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