Fork

When a single cryptocurrency splits due to changes to the rules used for the governance of an existing crypto-currency. Different parties need to use common rules to maintain the blockchain or the underlying code of a crytpo-currency. When parties disagree on a rule or set of rules, alternative chains (crypto-currencies) may emerge. Notable forks include Bitcoin (BTC) and Bitcoin Cash (BCH), and Ethereum (ETH) and Ethereum Classic (ETC).