22 terms explained

Payment Glossary: key terms explained

Plain-language definitions of the most important payment security, tokenization and PCI DSS terms. From payment tokens and card vaults to 3D Secure, IC++ pricing and SAQ requirements, find every term you need in one place.

Payment tokens Card vaults 3D Secure SAQ A vs SAQ D IC++ pricing Payment orchestration
Payment Infrastructure

Payment Infrastructure Terms

Key players and concepts in the payment processing ecosystem explained.

What Is a Payment Gateway?

Gateway

Routes transaction data between merchant, acquirer and card network. The merchant-facing entry point for card payments.

What Is a Payment Processor?

Processor

Handles authorization and settlement of card transactions between merchants and issuing banks on behalf of acquirers.

What Is an Acquirer?

Acquirer

The bank or financial institution that processes card payments on behalf of a merchant and settles funds into the merchant account.

What Is an Issuer?

Issuer

The bank or financial institution that issues payment cards to consumers and approves or declines transactions.

What Is a Card Scheme?

Card Scheme

Network that sets the rules and connects issuers and acquirers. Examples include Visa, Mastercard, and American Express.

What Is a Merchant ID?

MID

A unique identifier (MID) assigned by an acquirer to each merchant location to identify transactions during authorization.

What Is a Chargeback?

Chargeback

A forced transaction reversal initiated by the cardholder through their issuing bank to dispute a payment.

What Is Payment Fraud?

Fraud

Unauthorized use of a payment method for financial gain. Tokenization significantly reduces card fraud exposure.

What Is a CVV?

CVV

A 3 or 4 digit security code printed on a payment card used to verify card-not-present transactions.

What Is End-to-End Encryption?

Encryption

Encrypts card data from the point of capture all the way to the secure processor so it cannot be read in transit.

What Is a Hardware Security Module?

HSM

A tamper-resistant hardware device used to generate, store and manage cryptographic keys for payment systems.

What Is AVS?

AVS

A fraud prevention tool that checks the billing address provided at checkout against the card issuer records.

What Is Strong Customer Authentication?

SCA

An EU payment regulation (PSD2) requirement for multi-factor authentication on electronic transactions.

What Is 3DS2?

3DS2

The latest version of the 3D Secure authentication protocol supporting risk-based, frictionless authentication flows.

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Why these terms matter for your business

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