Taproot
Also: BIP-341
cryptography · advanced
Bitcoin's 2021 soft-fork upgrade. Schnorr signatures, a unified address format for single-sig and complex scripts, and significantly better privacy for cooperative spends.
Taproot activated at block 709,632 in November 2021. It bundled three BIPs: 340 (Schnorr), 341 (Taproot output construction), and 342 (Tapscript). The combined effect: a v1 segwit output type ("bc1p...") that can be spent two ways.
The "key path" looks like a single Schnorr signature — no matter how complex the underlying conditions. The "script path" reveals the specific script being executed, but only the one actually used; alternate branches stay hidden. So a multisig vault with cooperative-spend, recovery-spend, and emergency-spend branches looks on-chain like an ordinary single-sig payment whenever everyone cooperates.
In practice this gives Bitcoin a meaningful privacy upgrade: complex policies become invisible until disagreement forces them on-chain. Combined with MuSig2, even n-of-n multisig becomes indistinguishable from single-sig. Adoption has been gradual — most exchanges support sending to Taproot, fewer support receiving, and Lightning Taproot channels are still being rolled out.