Digital signature
A value that proves a message was produced by the holder of a particular private key and has not been altered since. Signatures provide authenticity and integrity, not confidentiality.
Related terms
The NIST-standardised lattice-based digital signature algorithm, intended as the general-purpose post-quantum replacement for RSA-PSS and ECDSA. Signatures are larger than ECDSA but performance is practical for most uses.
The signature scheme used by Bitcoin, Ethereum and most blockchains, based on elliptic curves such as secp256k1. It is not post-quantum: Shor's algorithm would recover the private key from an exposed public key.
Cryptography using a mathematically linked key pair: a public key that can be shared, and a private key that must not be. It is the part of modern cryptography that quantum computers threaten most directly.