What Is a Fork (Blockchain)?
A fork in the blockchain is a situation where two miners find blocks at nearly the same time. This creates a temporary split in the chain, as both miners will be competing to extend their own version of the chain with new blocks. The network then decides which branch is valid and continues extending it, while discarding any invalid branches. In some cases, this can lead to a permanent split in the blockchain known as a hard fork.
Hard forks are used when developers want to make changes or updates to an existing cryptocurrency protocol that would not be compatible with previous versions of its software. When this happens, all users must upgrade their software so they can continue participating on the network and using its features properly. Hard forks also create opportunities for new coins or tokens if developers decide to use them as part of their update process. For example, Bitcoin Cash was created after Bitcoin underwent a hard fork in 2017 due to disagreements among members of its community about how best to scale its technology for more widespread adoption.