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.

The Bitcoin Price Index (BPI) is an averaged indicator of the value of bitcoin, calculated from the data of several major exchanges. It helps to assess the market price without being tied to a single venue.

An output is the part of a Bitcoin transaction that sets the recipient's address and the transfer amount. A single transaction can have several outputs at once: for different recipients and to return change to the sender.

A block reward is the payment a miner receives for a successfully created block of transactions added to the blockchain. It consists of new coins and transaction fees.

The genesis block is the very first block in a blockchain, from which the network's history begins. It lays the foundation for all subsequent blocks and effectively marks the birth of a cryptocurrency.