Public-key cryptography in the blockchain

Blockchains are designed to be pseudonymous, meaning your identity on the blockchain is your blockchain "address" and these addresses are derived from a user's public key

Beyond implementing identity, public-key cryptography is used for digital signatures:

• Transactions are signed to prove that they are approved by the owner of an address

• Blocks are signed by their creator

Since the blockchain is decentralized and pseudonymous, these signatures protect the integrity of the digital ledger