text: Bitcoin is a decentralized digital currency, without a central bank or single administrator, that can be sent from user to user on the peer-to-peer bitcoin network without the need for intermediaries. Transactions are verified by network nodes through cryptography and recorded in a public distributed ledger called a blockchain.
  Bitcoin is unique in that there are a finite number of them: 21 million.
  Bitcoins are created as a reward for a process known as mining. They can be exchanged for other currencies, products, and services.
   As of February 2015, over 100,000 merchants and vendors accepted bitcoin as payment..
  According to research produced by Cambridge University there were between 2.9 million and 5.
  8 million unique users using a cryptocurrency wallet, as of 2017, most of them using bitcoin..
  Bitcoin has been criticized for its use in illegal transactions, its high electricity consumption, price volatility, thefts from exchanges, and the possibility that bitcoin is an economic bubble.
  Bitcoin has also been used as an investment, although several regulatory agencies have issued investor alerts about bitcoin.
  The domain name “bitcoin.org” was registered on 18 August 2008. In November 2008, a link to a paper authored by Satoshi Nakamoto titled Bitcoin: A Peer-to-Peer Electronic Cash System was posted to a cryptography mailing list.
  Nakamoto implemented the bitcoin software as open source code and released it in January 2009. Nakamoto’s identity remains unknown..