Affiliate programs pay web site owners (host sites) for sending people to their sites through referral links/banner ads. Affiliate programs use a web application to allow host sites to track the results of their participation. The affiliate program will assign the host site an ID and provide instruction on how to set up links. Links are typically in the form of banner ads or sent in e-mails.
 
Payment is typically based on:

• Click through: Number of visitors that travel to the affiliated site.
• Leads: The number of visitors that fill out a survey
• Purchases: Commisions payed on sales generated from affiliate traffic