Hard Fork

    A hard fork is a software update that is incompatible with previous versions. A hard fork occurs in the context of blockchain technology when new rules are introduced into the blockchain code that is incompatible with the rules of the blockchain’s previous code. If network nodes do not update their software, they will be unable to communicate with nodes that have. This can cause the blockchain to split into two networks, one that follows the old rules and one that follows the new, updated rules. For example, Bitcoin Cash arose as a result of a hard fork in the Bitcoin blockchain.