On 25 September 2011, developer Amir Taaki suggested on the Bitcoin development mailing list that Bitcoin’s formal change documents should be called Bitcoin Improvement Proposals (BIPs). The BIP process is the public specification system used to propose, discuss, and document changes to Bitcoin. Individual BIPs are numbered papers covering protocol rules, peer-to-peer behavior, wallet standards, and process conventions. Later upgrades such as Segregated Witness and Taproot were specified through this system. Taaki’s idea is still used 15 years later. The documents live in an open repository, are debated in public, and are adopted only if implementations and the network follow them. The mailing-list note did not create Bitcoin’s governance. It named one of the formats through which that governance is written down.