Credit memos is very helpful, when customer wants Partial or Full Refund of his order amount. The Admin can either convert the amount as a store credit for next purchase or the refund the amount which is transferred back to the customer credit card account. The credit memos need to be generated first before printing the credit memo document. The store owner have option to generate one or multiple credit memos. The credit memos grid in the Order view shows all the credit memos generated against the order.
There are different methods using which store owner can issue refunds, it depends on the payment method that is used to placed the sales order.
Some of the orders Refund Online like the orders placed using Paypal, Credit/Debit Card. While the others orders are Refunded Offline like Cash On Delivery or Check/Money Order.