Bitcoin is an open-source, peer-to-peer, digital decentralized cryptocurrency. Powered by the Blockchain technology, its defining characteristic is its decentralization, i.e. the lack of central governing authority, such as a central bank or a ministry of finance. Bitcoin's issuance and circulation are ensured by regular users via a process known as "Bitcoin mining". Bitcoin can be sent anywhere, anytime, (almost) for free, and with little regard for national borders or government/bank-imposed restrictions.
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