Vouchers allow you to sell gift cards through resellers such as Tuango.ca, Groupon, etc. Their customers usually buy their voucher at a discounted price and then redeem it for a gift card on your site.
For example, a customer of the discount site Tuango.ca purchases a voucher valid for a $200 gift card. The customer receives an alphanumeric code like this: X0EF34. The customer can then go to your site to convert the code into a gift card, which will be worth $200.
Please read the article on promotional values carefully to understand the effect when a customer gets more value than the price paid.
