What is the difference between voiding and refunding a payment?

Refunding occurs only after a payment is finalized and committed, or captured. In this event, the funds that were previously deducted will be returned to the customer's bank account.

Voiding occurs only after a payment is authorized but before it is captured, that is, while the funds have not yet been deducted from the customer's account. As a result of a 'void' action, funds that were authorized and set aside to be captured will be released and unauthorized.