Segwit, or Segregated Witness, is a protocol upgrade to the Bitcoin network that was activated in August 2017. It was created to address the scalability issues that Bitcoin was facing due to its growing user base. Segwit works by separating transaction signatures (witnesses) from the rest of the transaction data, which are then stored in a segregated area of the Bitcoin blockchain.

The primary benefit of Segwit is to reduce the amount of data that is stored on the blockchain, thus allowing for more transactions to be processed in a shorter amount of time. This is done by removing the signature data from the transaction data, making the transaction smaller and faster to process. Additionally, Segwit also contains a few other improvements, such as transaction malleability fixes, which make it more secure.

Segwit also enables a new type of transaction, known as a pay-to-witness-script-hash (P2WSH) transaction, which allows users to store complex scripts on the blockchain. This opens up the possibility for new types of applications, such as multi-signature wallets, and allows for more advanced transaction types.

Overall, Segwit is a major upgrade to the Bitcoin network, and it offers a range of benefits that help to improve the scalability and security of the network. It is a key part of the Bitcoin scaling roadmap and will help to ensure that the network is able to grow and meet the needs of its users in the future.