Glossary
In this page we list some terms that are used throughout the documentation and define exactly what they mean in the context of this API.
Acquirer
The company that processes the payment for the merchant. They are responsible for the communication with the card networks and the banks.
Cashier
The person who is serving the customer and operating the client through a user interface.
Client
The system that the merchant uses to talk to the terminal through the API.
Customer
The person who is buying the product or service and operating the terminal.
DCC
DCC (Dynamic Currency Conversion) is a service that allows customers to pay in their own currency. The amount in the transaction is converted to the customer’s currency at the time of the transaction. The conversion rate may vary depending on the payment method and the provider.
Merchant
The company that is selling the product or service.
Payment instrument
Something that the customer uses to pay for the product or service. This can be a card, a mobile phone, or any other device that can be used to make a payment.
Payment method
The way that the customer pays for the product or service. This can be a card payment, regardless if the card is a physical card or a mobile phone, or any other method that is supported by the terminal. It can also be some alternative payment method, such as a QR code.
Release
All changes to the API are releases. It is identified by a release date, such as 2025-04-30.
Server
The Nexi system that serves the API. It talks to both the client and the terminal.
Simulator
A simulated terminal that can be easily and quickly created to allow clients to test different terminal behaviours. When using it, the server will not connect to any other systems but will behave the same as if it was a physical terminal. Every simulator is unique, so that clients do not interfere with each other.
Terminal
The physical payment device that the customer interacts with.
Version
The version of the API that is used. It is identified by a version number, such as v0.