There are many marketing ways through which any seller try to sell or promote its products. One of the very effective marketing option is affiliate marketing.
Major source of income for any coupon site is affliliate marketing. Affiliate marketing is a by which for every sale the affiliate make commission and commission would range from 0.01 and upto 100% and depends on item sold. Amazon is one of the largest paymaster to its affiliates. In US alone thousands of people make their living through affiliate marketing with Amazon.
Once you register with any seller as an affiliate partner you get an affiliate link and if anyone visits the seller site through that affiliate link and buys any item, it is recorded as a sell through the affiliate partner and commission as per structure is added for the payout.