BIP
A BIP (Bitcoin Improvement Proposal) is a formal document proposing a change or addition to the Bitcoin protocol. BIPs are the primary mechanism by which technical upgrades, standards, and processes are proposed, discussed, and adopted by the Bitcoin community.
A Bitcoin Improvement Proposal is a design document providing information to the Bitcoin community, or describing a new feature for Bitcoin, its processes, or its environment. The format was adapted from Python's PEP system and first formalized by Amir Taaki in 2011 as BIP 1. Every BIP is assigned a number and published in a public repository. There are three types: Standards Track BIPs (proposing protocol-level changes such as soft forks), Informational BIPs (guidelines and best practices), and Process BIPs (changes to development procedures). Any developer can write and submit a BIP.
For a Standards Track BIP to be adopted, it must achieve broad consensus among the network's participants. No central authority can force through a change. Node operators, miners, wallet developers, and the wider community all play a role in deciding whether to activate a proposal. This decentralized governance is intentional: it makes Bitcoin resistant to unilateral changes by any single group, including core developers. Notable BIPs include BIP 32 (hierarchical deterministic wallets), BIP 39 (mnemonic seed phrases), BIP 141 (SegWit), BIP 173 (bech32 addresses), and BIP 340-342 (Taproot).
The BIP process means that Bitcoin evolves slowly and deliberately. Controversial proposals can remain open for years while debate continues. This conservatism is often criticized as slow, but defenders argue it reflects the high cost of consensus rule changes in a system where mistakes cannot easily be reversed. A change rejected by even a minority of node operators risks splitting the network into two chains, as happened with Bitcoin Cash in 2017.