Keywords/phrases: What is the difference between Bitcoin and the blockchain(s)? Proof of Work is an essential feature for many aspects of Bitcoin. PoW, not openness, brings immutability. Immutability is not the same thing as unforgeability. Anonymity prevents coercion. Permissioned ledgers are vulnerable to extortion. Bitcoin sacrifices transaction efficiency to give you freedom, global access, permissionless innovation, and censorship resistance.