An acquirer is a financial organisation that provides facilities for businesses to accept payments and receive funds.

An Application Programming Interface is a particular set of rules and specifications that software programs can follow to communicate with each other.

An address verification service is a fraud prevention tool that checks the shopper's address and postcode.

The callback is the URL used to process payment responses that are displayed to shoppers.

Chargeback is a sum of money deducted by a credit card company from your account to cover losses for disallowed or fraudulent transactions.

Card-not-present, a term used to describe a merchant situation where the consumer makes a card transaction without being physically present.

Card verification codes or card verification values are three digit numbers printed on the back of debit and credit cards and are used to check that the card is physically in the possession of the cardholder.

Dynamic currency conversion is a service in which holders of credit or debit cards have the cost of a transaction converted to their local currency when making a payment in a foreign currency.

An electronic wallet is an encrypted storage medium which holds credit card and other financial information that can be used to complete transactions.

Electronic Commerce Indicator indicates the 3-D Secure status of a transaction.