Issuer - The bank, credit union or other financial institution that issues credit and debit cards to consumers. Once a card transaction has started and routed to the issuer through the card scheme, the issuing bank will have to determine whether they have enough funds or credit to cover the amount requested. If the transaction is authorised, they are responsible for billing the cardholder for his purchases.
Acquirer - The financial institutions that connect merchants with card schemes by routing the card transaction through the relevant scheme. Also known as an acquiring bank.
Client - system or person interacting with the payment gateway.
Payer — a natural or legal person who makes a payment with his card for the services of a merchant in payment gateway.
Order - the elementary essence of the payment gateway describing an order in some online store or its analogue.
One-step payment —One-step payment – a transaction for payment of goods/services made using bank cards, which does not require additional confirmation (one request initiates simultaneous blocking and debiting of funds from the card). This type of payment is preferable if the product or service is provided immediately after payment.
Two-step payment — transaction for payment of goods/services that requires additional confirmation (Completion), i.e. payment is made in two stages. At the first stage, the availability and blocking of the payer's funds is checked (pre-authorization); then, in the second stage, the company either confirms the need to write off funds or cancels the blocking of funds. The debit amount may differ slightly from the blocking amount.
Hold (Blocking funds) - The state of the amount of funds intended for reimbursement of the transaction, from the moment of successful authorization to the moment of completion of settlements between participating banks. At this stage, the funds are still in the payer's account, but are no longer available for use on the card.
Refund — Refund is a financial transaction where a previously processed payment is reversed, and funds are returned to the customer. Typically initiated by a merchant, a refund can be triggered for various reasons, such as product returns, cancellations, or resolution of disputes.
Reversal — A payment reversal is the return of funds to a cardholder's bank account. Payment reversals can be initiated for various reasons, such as fraud, out-of-stock items, funds taken out for the wrong amount, or product returns.
3D Secure (3DS) — protocol of additional authentication of the Payer, based on the concept of three domains: acquirer, issuer and compatibility. 3D Secure (3DS) is an additional layer of security in online credit and debit card transactions. This protocol is designed to authenticate the cardholder's identity during the payment process, reducing the risk of unauthorized transactions and fraud liability for merchants and issuers. The process involves three key participants - a cardholder, a merchant, and an issuer. Once customers enter their card details, they are redirected to a page where they must enter a one-time code sent to their mobile or email.
