Re: How exactly does hardfork work ? How can I study about it?
A fork normally happens when theres a change in the consensus rule. When that happens youll see the chain split into two (imagine a Y).
The 'Y' is used for imagination. In reality there is no real split.
Each node stores its own copy of the blockchain. When a hard fork occurs there are basically 2 versions of the blockchain spread between nodes.
Both versions have the same data until block X. The representation with an 'Y' seems to be the most popular one. But from block X those are 2 completely independent networks.
Take bitcoin cash for example. They forked the chain by increasing the blocksize to 4mb. The nodes on the main chain wont be able to validate that because they can only accept blocks up to 1mb.
They increased the blocksize to 8mb.
Litecoin is not a fork because they didnt branch out of the main chain. They started all over.
It is not a fork in terms of 'blockchain forks', but bitcoins code on github got forked.
This is visible at the top left corner of LTC's github (https://github.com/litecoin-project/litecoin):
