Pay-Per-Click (PPC)
The PPC is the most common type thanks to the popularity of Google AdSense/Adwords. This PPC is when a Advertiser pays the Publisher for a click (sometimes refered to as a ‘click-through’). This type is often more beneficial to the Publisher as a click is often very easy to obtain from the user.
Pay-Per-Sale (PPS)
This is a more common type among affiliate networks. This is can be either a % of the overall sale or a set amount for a sale. The user has to navigate to the Advertiser’s website by clicking on the advertisement on the Publisher’s website, once the user is on the website they need to make a purchase and the Publisher will either recieve % amount of the sale or a set amount. This is more beneficial for the Advertiser as they are not paying for someone to browse their website but are paying when someone buys from them. This can often also be very beneficial for Publisher as instead of a less than a dollar for a click you can make a large amount from one purchase depending on the % amount or set amount.
Pay-Per-Lead (PPL)
The PPL is a concept in which is normally used when there is not much money involved initially but there is an on-going amount, i.e. a credit card. For something like this there is not really any money involved so for a Publisher to recieve a % of the sale is pointless, but instead they recieve a ‘Pay’ for a sales lead. This is also more beneficial to the Advertiser than the Publisher. But can sometimes be very beneficial to the Publisher compared to the small amount of a ‘Pay’ in PPC.
Publisher
This is the website who shows the advertisement.
Advertiser
This is the website who creates the advertisement and pays the Publisher to show it.
User
This is the person that comes to the website and will click an advertisement.

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