Learning What It Is Bitcoin

Bitcoin is a cryptocurrency and worldwide payment system.[9]:3 It is the first decentralized digital currency, as the system works without a central bank or single administrator.[9]:1[10] The network is peer-to-peer and transactions take place between users directly, without an intermediary.[9]:4 These transactions are verified by network nodes through the use of cryptography and recorded in a public distributed ledger called a blockchain. Bitcoin was invented by an unknown person or group of people under the name Satoshi Nakamoto[11] and released as open-source software in 2009.[12]

Bitcoins are created as a reward for a process known as mining. They can be exchanged for other currencies,[13] products, and services. As of February 2015, over 100,000 merchants and vendors accepted bitcoin as payment.[14] Research produced by the University of Cambridge estimates that in 2017, there are 2.9 to 5.8 million unique users using a cryptocurrency wallet, most of them using

bitcoin.

Denominations

Plural bitcoins

Symbol ₿[a]

Ticker symbol BTC, XBT[b]

Subunits

1⁄1000 millibitcoin[1]

1⁄1000000 bit[3][better source needed]

1⁄100000000 satoshi[4]

Coins Unspent outputs of transactions (in multiples of a satoshi)[5]:ch. 5

Development

Original author(s) Satoshi Nakamoto

White paper Bitcoin: A Peer-to-Peer Electronic Cash System[6]

Implementation(s) Bitcoin Core

Initial release 0.1.0 / 9 January 2009 (9 years ago)

Latest release 0.15.1 / 11 November 2017 (3 months ago)

Website bitcoin.org

Ledger

Ledger start 3 January 2009 (9 years ago)

Timestamping scheme Proof-of-work (partial hash inversion)

Hash function SHA-256

Issuance Block reward[7][8]

Block reward ₿12.5[c]

Block time 10 minutes

Block explorer blockchain.info

Circulating supply ₿16,858,762 (as of 11 February 2018)

Supply limit ₿21,000,000

Valuation

Exchange rate Decrease US$8,660 (as of 12 February 2018)

Market cap Decrease US$146.4 billion (as of 12 February 2018)

The symbol was encoded in Unicode version 10.0 at position U+20BF ₿ BITCOIN SIGN in the Currency Symbols block in June 2017.[2]

Compatible with ISO 4217.

July 2016 to approximately June 2020, halved approximately every four years