2/ What is a fork?
A (hard) fork refers to a change in a blockchain protocol that results in two blockchains - one that follows the previous protocol & one that follows the new version. The new chain shares all of its previous history with the original.
什么是叉子？
（硬）分叉是指区块链协议中的变化，导致两个区块链-一个遵循之前的协议&；新版本之后的版本。这家新连锁店与原连锁店有着相同的历史。