Users management their bitcoin through a digital signature system by which they indicate consent to transfer cash. These digital signatures are public, cannot be solid, and could be verified by anyone. It is important that there’s just one model of the transaction ledger because to find a way to verify a payment, participants have a look at the ledger to validate that an amount of bitcoin has certainly been transferred. If there were totally different ledger histories, a malicious person would possibly be succesful of ‘double spend’, i.e. transfer a single bitcoin greater than as soon as, as two payments.