Cryptocurrency markets are decentralised, which means they are not issued or backed by a central authority such as a government. Instead, they run across a network of computers. However, cryptocurrencies can be bought and sold via exchanges and stored in ‘wallets’ . Unlike traditional currencies, cryptocurrencies exist only as a shared digital record of ownership, stored on a blockchain. When a user wants to send cryptocurrency units to another user, they send it to that user’s digital wallet. The transaction isn’t considered final until it has been verified and added to the blockchain through a process called mining. This is also how new cryptocurrency tokens are usually created. A blockchain is a shared digital register of recorded data. For cryptocurrencies, this is the transaction history for every unit of the cryptocurrency, which shows how ownership has changed over time. Blockchain works by recording transactions in ‘blocks’, with new blocks added at the front of the chain.