if bitcoin is hackable why is the value going up and bitcoin is still existing? bitcoin is compose of a lot of transactions called blockchain, blockchain is a ledger of records arranged in data batches called blocks that use cryptographic validation to link themselves together. Put simply, each block references and identifies the previous block by a hashing function, forming an unbroken chain, hence the name. every account is encrypted with pass phrase or keys that only you the owner know that why it is secured. you will be hacked if you reclesly give your passphrase or keys to anyone.