Bitcoin cash was flourished by bitcoin miners and developers by changing bitcoin protocol because of the bitcoin blocks that were difficult to mine or the transactions that were not able to be performed. Bitcoin cash made transactions to be done in a sleek manner. The developers who were not satisfied with the functions of blockchain performance brought new blockchain implementations to make it easier to transact and mine. All of this process of blockchain implementation alteration or renewal is called Hard Fork. All of the users and nodes are then required to upgrade to newest versions of the blockchain softwares. In easiest way its when the new version of the blockchain does not recognize the old version of blockchain.
Function of Hard Fork:
Fork works just like signals or the boards on the roadside to guide people. Just like that developers are told to implement the new rules and functions.
Bitcoin Cash:
Solution to the invalid transactions and cryptographic block mining came through as bitcoin cash when hard fork was implemented which made transaction and mining of the blocks easy i.e 8 MB to increase the speed of transaction verification. Where as, bitcoin transactions had speed of only 1 MB. But BCH has less marketcap and liquidity then bitcoin as bitcoin rules the crypto markets.
