What is a hard fork in cryptocurrency?

A hard fork is a significant and incompatible change to a cryptocurrency’s protocol that creates a divergence in the blockchain, resulting in two separate chains. A hard fork typically occurs when there is a major disagreement within the community about the future direction of the cryptocurrency. It can lead to the creation of a new cryptocurrency that shares the same transaction history up to the fork point but diverges thereafter. For example, Bitcoin Cash was created through a hard fork from Bitcoin in 2017. While hard forks can offer innovation and improvements, they can also cause divisions within the community and confusion among users.