Bitcoin has been designed to increase in value over time. This is because the total amount of bitcoins available will never exceed 21 million coins. For money to be usable when it appreciates more, we must break it down into smaller units. So, if the value of a single bitcoin increases by several thousand dollars, we can still use it to shop for the smallest thing we can find on the Internet. Satoshi is currently the smallest bitcoin unit. The unit was named in tribute to the original creator(s) of Bitcoin, Satoshi Nakamoto.