Understanding Bitcoin Sub-Units
Bitcoin is divisible down to 8 decimal places. The smallest unit on the base protocol layer is known as a Satoshi, named in honor of Bitcoin’s pseudonymous creator Satoshi Nakamoto.
Educational Note: On Layer 2 payment networks like the Lightning Network, value can even be divided into Millisatoshis (msat), which represent one-thousandth of a satoshi (0.00000000001 BTC), enabling microscopic streaming payments.