The private key in blockchain is a code used to solve messages encrypted to users that can only be available to them.
What are the advantages of a private key? Increased security: the private keys do not ever need to be transmitted or revealed to anyone.
Can Blockchain Private Key be hacked? The only possibility of private keys being hacked comes from the threat of quantum computers. This is due to the fact that quantum computers can process much more information than just binary computation, which is the limit of classical computing systems. As a result, quantum computers can process many orders of magnitude more than classical computers. But realistically, such a threat is many years in the future. And most importantly, there is already a lot of development in quantum-resistant blockchains being made.