What is cpa?

I have heard alot about cpa and would like know what it is? Can someone please explain or give an example?

 

CPA stands for “Cost Per Action” or “Cost Per Acquisition”. It is an offer where the customer must fill out a form or download software from an advertiser. These forms can be anything from a single email submit, such as a free laptop offer, to much longer forms with multiple fields to fill out, an example would be a life insurance offer. Software downloads could be items such as emoticons, screensavers or toolbars.