Sometimes, there is confusion surrounding when an order has been "Pre-authorized" versus "Captured Payment". This generally comes up with Pre-orders (and sometimes back-orders), where the card is pre-authorized for validity and funds ahead of order fulfillment.
There is a big difference in these two, and how they sometimes show up on your Card Statements:
When a merchant creates a pre-authorization, the cardholder's credit limit is reduced by the amount of the pre-authorization until the pre-authorization is captured or expires. After pre-authorizing a payment, the merchant can capture (process) the payment or void the pre-authorization. Sometimes the pre-authorization expires on its own (usually after 30 days) if it has not been captured.
Some banks will show the pre-authorization amount on a statement, as "authorization only". This is not a billed amount. No funds have transferred with these. It is important to know the difference, as if an order fails to charge, it means no funds have been captured. If an order is not funded, it cannot be processed.
Banks have these systems in place for pre-authorization, and capture. Don't worry, we don't double-charge, or try to charge a second time. It is simply showing up as a pre-authorization.
Authorizations from businesses for pending or failed orders may be visible on your bank account temporarily. If the order doesn't come through, these are removed after a short time according to the policies of your bank.