What is a satoshi

A satoshi is the smallest unit of bitcoin, equal to one hundred-millionth of a single BTC (0.00000001 BTC), named after bitcoin's pseudonymous creator Satoshi Nakamoto.

It matters because bitcoin's price per coin can run into tens of thousands of dollars, so satoshis (often shortened to "sats") let people price, tip, and transact in amounts far smaller than a whole coin without dealing with long strings of decimals. Traders and app builders often quote fees or balances in sats for the same reason cents are more practical than fractions of a dollar.

For example, if 1 BTC trades at $60,000, one satoshi is worth $0.0006, and 1,000 sats would be worth about $0.60. Lightning Network payments, a fast bitcoin payment layer, are typically denominated in sats rather than BTC.