Records stored in any cryptocurrency Block Chain are encrypted. Therefore only the owner of a record can decrypt it to reveal their identity (using a public-private key pair). Therefore a person can use Blockchain but remain anonymous and ensure full transparency.
Therefore is Block Chain completely safe. Well, not 100% but to a large extent yes, it is hackproof. For a start, the bits of information are stored linearly and chronologically. In other words, new information is always added at the end of the Blockchain. Once a block had been added at the end of a Blockchain, it is literally impossible to alter it. It would require the majority of the nodes to also agree to execute the alteration. Also, each block carries its own hash, along with the hash of the block before it. Hash codes are essentially a mathematical function that converts digital information into a series of numbers and letters. If this series of numbers and letters are edited in any way, then the hash code changes as well.
Block Chain -Hack Proof
For example, a dark actor who is running a node in any Block Chain network wants to steal cryptocurrency owned by someone else. He could alter only his copy and it will not align with everyone else’s copy. When the others cross-check, they will zero on the hacker’s version and will be treated as illegal.
To carry out a swindle the hacker will have to employ a massive amount of money and resources to simultaneously charge 51% of the nodes with his copy. It would require rehashing all the blocks because each will have its different timestamps and hash codes.
The size of cryptocurrency is gargantuan and it operates very fast and the money and resources to pull out this feat are not humanely possible. It would require computation in a gigantic scale and the cost will outgrow the results. It will also not remain undetectable and on the realization that a hack has been effected the community will affect a hard fork to a new version of the chain and the hacked version will lose all its value and become a worthless asset.