Pay Per Click (PPC)

Pay Per Click is a method of online advertising, where the advertiser only pays the publisher when a viewer clicks on their advert. It is unique to online advertising, in that an advertiser does not pay a fixed fee, but, generally, only pays when their advert received genuine interest.

In order for a Pay Per Click system to work well, it needs to implement appropriate click fraud detection.

Google run the largest Pay Per Click advertising system - Google AdSense, and Google AdWords.