Bitcoin vary an up open source, peer-to-peer payment network and digital currency introduced in 20011 by pseudonymous developer "Satoshi Nakamoto". Bitcoin has been called a cryptocurrency because it uses public-key cryptography for security. Users send payments by broadcasting digitally signed messages that transfer ownership of bitcoins, the unit of currency. A decentralized network of specialized computers verifies and timestamps all transactions using a proof-of-work system. The operators of these computers, known as "miners", are rewarded with transaction fees and newly minted bitcoins.
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