Chain-key Bitcoin (ckBTC) is a token on the Internet Computer (ICP) that is backed 1:1 by bitcoin (BTC). Conversion and redemption is fully automated via canister smart contracts using threshold cryptography - no trusted intermediaries required.ckBTC transactions have a 1-2 second finality and incur negligible fees, making it a viable option for everyday economic activities such as buying groceries or getting a coffee.