Bitcoin is a digital currency created in 2009 by an individual or group using the pseudonym Satoshi Nakamoto. It is a type of decentralized cryptocurrency that allows for peer-to-peer transactions without the need for a central authority or middlemen. Bitcoin transactions are recorded on a public ledger called the blockchain, and are verified by miners who solve complex mathematical equations. Bitcoin has gained popularity as an alternative payment system and store of value, and its price can fluctuate greatly in relation to supply and demand.
Satoshi Nakamoto, 2009 — Bitcoin: A Peer-to-Peer Electronic Cash System