A signature scheme in Bitcoin activated in the Taproot upgrade with BIP 340. Schnorr signatures offer several advantages over ECDSA in terms of efficiency, scalability, and privacy.

Schnorr signatures enable native multi-signature transactions, which can be aggregated into a single signature, reducing blockchain bloat and transaction fees. Additionally, Schnorr signatures enhance privacy by making multi-signature transactions indistinguishable from regular transactions, and they simplify the implementation of more complex smart contracts.