SegWits

SegWits is an informal term used to describe the proponents and implementations of Segregated Witness (SegWit) in Bitcoin and related networks. SegWit is a protocol upgrade that separates the digital signatures (the witness) from the rest of a transaction. By moving witness data outside the base transaction, SegWit increases the effective block capacity and fixes transaction malleability, a vulnerability that could alter transaction IDs before confirmation.

Technical overview: In SegWit, transaction data and witness data are stored separately. The protocol uses a weighting system that counts base data more heavily than witness data, enabling more transactions per block without increasing the base block size. SegWit also enables new address formats (Bech32) and supports second-layer solutions such as the Lightning Network, which rely on malleability resistance and improved transaction throughput.

History and activation: SegWit was proposed in Bitcoin Improvement Proposals (notably BIP141) by Pieter Wuille and others, and activated on the Bitcoin network as a soft fork in August 2017 after extensive signaling. Its adoption occurred gradually as wallets, exchanges, and miners upgraded. A separate, high-profile plan known as SegWit2x was discussed in 2017 but never activated.

Adoption and impact: SegWit’s deployment has become standard in modern Bitcoin software. Bech32 addresses are widely supported, and many applications default to SegWit transactions. The upgrade reduced malleability risk and underpins scaling approaches, especially through second-layer solutions. As with any protocol upgrade, adoption varied across services and communities, but SegWit remains a foundational element of current Bitcoin transaction processing.