1
A blockchain is a sequence of transactions partitioned into blocks with properties of persistence (transactions cannot be removed) and consensus (agreement on the current set of transactions).
2
Digital signatures are crucial for implementing a cryptocurrency and consist of three steps: generating a key pair (public and private keys), signing messages with the secret key, and verifying signatures using the public key.
3
Common digital signature schemes used in cryptocurrency include ECDSA, Schnorr, and BLS signatures.
4
A Bitcoin address is derived by taking a public key and hashing it, resulting in a unique identifier where others can send funds.
5
The secret key must be kept secure (often stored on paper or as QR codes) and is strictly required to sign transactions and spend funds from an address.