BIP (Bitcoin Improvement Proposal)
BIP 341 — Taproot: SegWit Version 1 Spending Rules
Introduced Taproot, the most significant Bitcoin protocol upgrade since SegWit. By combining Schnorr signatures (BIP 340) with Merkelized Abstract Syntax Trees (MAST), Taproot makes complex spending conditions as private and efficient as simple payments, while enabling more sophisticated smart contracts.