A hard fork in cryptocurrency refers to a significant and permanent divergence in the blockchain network, resulting in the creation of a new and separate version of the blockchain.
It occurs when a cryptocurrency's existing protocol and rules are modified in a way that is incompatible with the previous version.
During a hard fork, the blockchain splits into two separate chains, each following its own set of rules. This leads to the formation of two distinct cryptocurrencies.
The original chain continues to operate as it did before the fork, while the newly created chain adopts the changes introduced by the fork.
Hard forks can be initiated for various reasons, such as implementing new features, resolving security vulnerabilities, or addressing disagreements within the cryptocurrency community regarding the future direction of the network.
These changes are typically proposed and implemented by the developers or community members who support the fork.
After a hard fork, holders of the original cryptocurrency receive an equal amount of the new cryptocurrency based on their holdings at the time of the fork.
However, it's important to note that not all participants in the network may agree with the changes, and there may be a division among community members, miners, and other stakeholders.
Examples of notable hard forks include the Bitcoin Cash fork from Bitcoin, the Ethereum Classic fork from Ethereum, and the Bitcoin SV fork from Bitcoin Cash.