Hard Fork

Hard Fork is a significant change in a blockchain's protocol that renders previous versions incompatible. It creates a divergence in the blockchain, resulting in two separate chains with different rules. This often occurs to address security issues, add new features, or reverse transactions. Participants must upgrade their software to continue interacting with the new chain. A hard fork can lead to the creation of a new cryptocurrency if there is disagreement within the community. Examples include Bitcoin Cash from Bitcoin and Ethereum Classic from Ethereum after such events.