Bitcoin (BTC) is a digital currency first described in a 2008 paper by pseudonymous developer Satoshi Nakamoto, who called it a peer-to-peer, electronic cash system. Bitcoin creation and transfer is based on an open source cryptographic protocol and is not managed by any central authority. Each bitcoin is subdivided into 100 million smaller units called satoshis, defined by eight decimal places. Bitcoins can be transferred through a computer or smartphone without an intermediate financial institution.