A payment service provider (Payment Service Provider, PSP) is a service that allows payments to be accepted and sent by various methods, combining many payment methods in a single interface for businesses and users.

A QR code is a two-dimensional graphic image that encodes data and is read by a camera; in cryptocurrencies it is used to quickly transmit addresses and payment details.

A merchant is a trade or service business that accepts payment cards and, in many cases, cryptocurrencies. The term comes from the English word merchant.

A merchant account is a special trade account for a business used to accept non-cash payments by cards and over the internet. It links the seller to the payment infrastructure and the acquiring bank.

A microtransaction is a payment of a very small amount, often less than the minimum monetary unit. Such operations are unprofitable for traditional payment systems because of fees, while cryptocurrencies make them feasible.