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.

A millibitcoin (mBTC) is one thousandth of a bitcoin, that is, 0.001 BTC. This fractional unit is used to conveniently display small amounts in this cryptocurrency.

Mt. Gox is one of the first and largest Bitcoin exchanges, based in Japan. Its closure after a major loss of funds became one of the most famous events in the history of cryptocurrencies.

Multisignature is a technology in which carrying out a transaction requires not one but several signatures with different private keys. It noticeably increases the security of storing crypto assets.