What is CPA?
Internet Marketing Dictionary | Cost Per Action

Cost per action or CPA is a method of monetizing your web traffic. You set up links that go via a CPA network to a sales or subscription page on an advertiser's website. If someone clicks the link on your page or in your email and then goes on to make a purchase or to sign up and provide their contact details then you get paid. You only get paid if the appropriate action is taken. You don't get paid for the traffic.

From the advertiser's point of view the advantage of using CPA networks is that they only pay out money when a specific event happens. From the marketer's perspective the advantage of CPA networks is that the payout per action can be very high.

CPA networks are websites that link advertiser's to web site owners. In return for this they take a commission on all successful transactions.  If you have the right sort of traffic that is relevant to specific CPA campaigns you can make very significant commissions. One thing to watch out for is that many CPA offers are restricted to specific geographic locations. This means that you will only get paid if the appropriate action is taken by someone onthe right country.

There are many CPA networks and most publishers use several to make sure that they are able to put the most profitable and highest converting offers in front of them. Good CPA networks will provide you with detailed reporting statistics so that you can find out which advertising campaigns are making you most money.