Actually, affiliate marketing systems are pay per click affiliate programs that work by paying to the website a small amount over the incomes of products and services sold by the affiliate. In general, this commission ranges from $0,01 to $0,20, which although may seem too few at first glance, still moves an amazing amount of money on the whole affiliate market everyday. Such prices may vary accordingly to how much the subject of the site (or the keywords in the advertisement) is searched through engines such as Yahoo or Google.

Inside the affiliate marketing, there are respective automatic systems in which the webmaster is also affiliated with internet search engines. Both Google and Yahoo, probably the biggest and most visited engines today, offer this type of affiliate program: Google with a service called Adsense and Yahoo with Overture. Let's see a brief explanation of each one of such affiliate programs:

Google Adsense: this type of affiliate program allows the posting of image and text ads in your website. They are created and administrated by Google itself, generating revenue that's based on the amount of clicks the ad receives through your website. It has been pointed out as one of the best affiliate programs available on the affiliate marketing today, since it allows the website to publish ads that are very less intrusive than others such as banners or pop-up windows (targeted as one of the main reason by which a regular online visitor stops visiting websites). Google utilizes its advanced search technology to determine what kind of ads shall be published in the website based on its content, location and other factors.

Yahoo Overture: This pay per click affiliate program run by Yahoo works in a very similar way that Adsense, with researches pointing the service as reaching 80% of all internet users. This affiliate program also delivers ads to the affiliate websites based on keywords that are searched in Yahoo's engine. Differently from Adsense and other less popular services, Overture charges a minimum of $20 by month to program use. Yet, the system uses search results from sites such as Ask Jeeves, MSN, and Lycos, providing a broader range of visits.