Cryptocurrencies like Bitcoin and Ethereum are open-source projects that rely on consensus over authority. This means that developers can tinker with the source code, creating problems if they cause disagreement within the community. Some cryptocurrencies have developed systems to avoid splits in the community to deal with this.
Blockchain forks can be thought of as a type of blockchain divergence. A fork in a blockchain occurs when different users have different versions of the existing blockchain and want to pursue their paths forward with the same data set. This leads to a situation where there are now two or more parallel blockchains that share a common history up to the point of divergence.
A blockchain fork is essentially a split of the network, where two blockchains are created after a certain point in time. This can happen when there’s a disagreement within the community over which changes should be implemented to the blockchain.
In most cases, this leads to a “hard fork,” which means that the new blockchain is incompatible with the old one, and miners and users have to choose sides.
A blockchain fork can happen when there’s a disagreement among miners or users about the proposed changes to the blockchain. For example, if some miners want to increase the size of blocks while others want to keep them at their current size, this could lead to a split in the network.