Fork

A fork occurs when a blockchain’s underlying protocol or rule set is changed, creating a divergence, or split, between the original chain and a modified version, sometimes resulting in two separate blockchains running independently going forward. Forks are a natural consequence of open-source, community-governed software, where changes to the rules require broad agreement, and disagreement can lead to a genuine split.

There are two main categories of forks, distinguished by their technical compatibility. A ‘soft fork’ is a backward-compatible change to a blockchain’s rules, meaning nodes that haven’t updated to the new rules can still recognize and validate blocks created under the updated rules, allowing for a smoother, more gradual transition without necessarily splitting the network. A ‘hard fork,’ by contrast, introduces changes that are not backward-compatible, meaning nodes running the old software will reject blocks created under the new rules entirely, effectively creating two separate, incompatible blockchains if a portion of the network’s participants choose not to upgrade.

Hard forks can happen for different reasons. Some are planned, non-controversial protocol upgrades where the entire community agrees to migrate to new rules together, with the old chain simply being abandoned once the transition is complete. Others result from genuine, unresolved disagreement within a project’s community about its future direction, leading a portion of participants to continue running the original rules while another portion adopts the new ones, creating two permanently separate blockchains and communities going forward.

Bitcoin Cash, which split from bitcoin in 2017 over disagreements about block size and scaling approach, is one of the most well-known examples of a contentious hard fork resulting in two separate, ongoing cryptocurrencies. When such a split occurs, holders of the original cryptocurrency at the time of the fork typically receive an equivalent balance of the new forked coin as well, since the fork essentially duplicates the blockchain’s transaction history up to the point of the split.

For Kurdcoin users, understanding forks helps explain why certain cryptocurrencies share similar names or technical origins, and provides useful context for understanding how disagreements within decentralized communities, which have no central authority to resolve disputes, can sometimes result in entirely new, independent projects being created.