Cryptography plays a key role in securing cryptocurrency transactions by ensuring that the information exchanged is kept private, secure and tamper-proof. Cryptography creates a “digital envelope” for data so it can be securely stored and transmitted over the internet. This is done by scrambling the data so it is difficult for outsiders to decipher the contents of a transaction. Cryptocurrencies also use cryptography to verify the legitimacy of transactions, ensuring that money is not transferred twice and that records of ownership remain valid. Cryptography also provides protection against various forms of attacks, such as double-spending, which occurs when someone tries to spend the same amount of money more than once.