Bitcoin (sign: BitcoinSign.svg; code: BTC or XBT[7]) is a distributed, peer-to-peer digital currency that functions without the intermediation of any central authority.[8] The concept was introduced in a 2008 paper by a pseudonymous developer known as "Satoshi Nakamoto".
Bitcoin has been called a cryptocurrency because it is decentralized and uses cryptography to control transactions and prevent double-spending, a problem for digital currencies.[8] Once validated, every individual transaction is permanently recorded in a public ledger known as the blockchain.[8] Payment processing is done by a network of private computers often specially tailored to this task.[9] The operators of these computers, known as "miners", are rewarded with transaction fees and newly minted Bitcoins. However, new Bitcoins are created at an ever-decreasing rate.[8]

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