Forks are essentially the splitting of a blockchain network/community. A fork occurs when the original rules of a blockchain network are changed, intentionally or unintentionally.

Accidental fork

The accidental fork occurred when different miners discovered two new ones on the blockchain network at almost the same timeblock, the original blockchain network will be temporarily divided into two different chains. Therefore, miners will be split between the two chains, and until a new block is added to one of the chains and a longer chain is formed, the longer chain will eventually be retained and the other will be discarded.

What is mining? Why do miners participate in mining? Please refer to the entry: What is mining?

Intentional fork

Intentional fork refers to the situation where the blockchain rules are intentionally modified. Since old nodes may choose not to upgrade to the latest version for whatever reason, the original blockchain will be split into two depending on whether these nodes choose to upgrade to the latest version. Intentional forks can be further divided into soft forks and hard forks.

• A soft fork is often referred to as a backward-compatible update where old nodes recognize the new blocks as valid. Soft forks do not require all nodes to be upgraded to implement new rules.
• Hard fork, in contrast, requires all nodes to upgrade to the latest version. This latest version is not backwards compatible, so a Brand new blockchain. A typical example is the 2017 hard fork of Bitcoin into $BTC and $BCH, which was designed to solve the scalability issues of the original Bitcoin. Another example is the hard fork of Ethereum into $ETC and $ETH after the DAO Attack in 2016 in an attempt to recover lost funds.

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