A credit slip is first and foremost a written proof that a product has been returned. Most of the time, and that the user can use it as a voucher.
A voucher is a discount code which doesn't not have to be tied to a merchandise return or a refund, and which can take many more forms than a simple credit slip:
- a discount on an order (percentage).
- a discount on an order (amount).
- free shipping.
You can apply a voucher to all customers, and group of customers, or a single customer; you can set its expiration date;
A cart rule is basically an advanced version of a voucher: in addition to what a voucher could do in PrestaShop 1.4, the cart rules system introduced in PrestaShop 1.5 enables you to:
- Name the discount
- Allow the customer to use only a portion of the discount
- Assign priorities between cart rules
- Set the compatibility between cart rules
- Have the discount only work with some carriers
- Have the discount only work with a selection of products and/or categories and/or manufacturers and/or suppliers and/or attributes... or all of these at the same time if necessary!
- Have the discount be applicable for free shipping and/or a discount on an order and/or a free gift... or all of these at the same time if necessary!