Fork (Hard & Soft)
A change to a blockchain's rules — backward-compatible (soft) or chain-splitting (hard), occasionally minting entirely new coins.
A fork changes a blockchain’s protocol rules. A soft fork tightens rules in a backward-compatible way (Bitcoin’s SegWit and Taproot upgrades). A hard fork breaks compatibility — nodes must upgrade or split onto a separate chain. When communities genuinely disagree, hard forks create new assets: Bitcoin Cash split from Bitcoin in 2017; Ethereum Classic preserved the pre-DAO-hack Ethereum in 2016.
Forks are crypto’s governance mechanism of last resort — exit instead of voice. For holders, contentious forks historically credited both chains’ coins to existing keys, though replay risks and exchange policies made the details messy. The market, not the loudest faction, ultimately prices which fork “won.”