This is what allows customers to add products to their shopping cart, view / manage their cart, and so on. This process does use cookies to store the needed reference information for the customer. If a customer's web browser does not allow cookies, they will not be able to add any products, checkout, etc.

The first time a customer either, adds a product to their cart, or views the contents of their cart, the script will assign the reseller for the order. Once the reseller has first been assigned, it will not change. This allows the customer to stray off the member's web site, but the member will still receive credit for the order.