Bitcoin about # read with me#

Bitcoin
Bitcoin is a cryptocurrency and worldwide payment system.[8]:3 It is the first decentralized digital currency, as the system works without a central bank or single administrator.[8]:1[9] The network is peer-to-peer and transactions take place between users directly, without an intermediary.[8]: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[10] and released as open-source software in 2009.[11]
Bitcoin

Prevailing bitcoin logo
Denominations
Plural
bitcoins
Symbol
₿[a]
Ticker symbol
BTC, XBT[b]
Subunits
 ​1⁄1000
millibitcoin[1]
 ​1⁄100000000
satoshi[3]
Coins
Unspent outputs of transactions (in multiples of a satoshi)[4]:ch. 5
Development
Original author(s)
Satoshi Nakamoto
White paper
Bitcoin: A Peer-to-Peer Electronic Cash System[5]
Reference implementation
Bitcoin Core
Initial release
0.1.0 / 9 January 2009 (9 years ago)
Latest release
0.15.1 / 11 November 2017 (2 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[6][7]
Block reward
₿12.5[c]
Block time
10 minutes
Block explorer
blockchain.info
Circulating supply
₿16,770,512 (as of 29 December 2017)
Supply limit
₿21,000,000
Valuation
Exchange rate
US$14.516 thousand (as of 29 December 2017)
Market cap
US$243.4 billion (as of 29 December 2017)
^ 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
Bitcoins are created as a reward for a process known as mining. They can be exchanged for other currencies,[12] products, and services. As of February 2015, over 100,000 merchants and vendors accepted bitcoin as payment.[13] 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.[14]
Etymology
The word bitcoin first occurred and was defined in the white paper[5] that was published on 31 October 2008.[15] It is a compound of the words bit and coin.[16] The white paper frequently uses the shorter coin.[5]
There is no uniform convention for bitcoin capitalization. Some sources use Bitcoin, capitalized, to refer to the technology and network and bitcoin, lowercase, to refer to the unit of account.[17] The Wall Street Journal,[18]The Chronicle of Higher Education,[19] and the Oxford English Dictionary[16] advocate use of lowercase bitcoin in all cases, a convention followed throughout this article.
Units
The unit of account of the bitcoin system is bitcoin. As of 2014, ticker symbols used to represent bitcoin are BTC[a] and XBT.[b] Its Unicode character is ₿.[24]:2 Small amounts of bitcoin used as alternative units are millibitcoin (mBTC)[1] and satoshi. Named in homage to bitcoin's creator, a satoshi is the smallest amount within bitcoin representing 0.00000001 bitcoin, one hundred millionth of a bitcoin.[3] A millibitcoin equals 0.001 bitcoin, one thousandth of a bitcoin or 100,000 satoshis.[25]

History
Main article: History of bitcoin
On 18 August 2008, the domain name "bitcoin.org" was registered.[26] In November that year, a link to a paper authored by Satoshi Nakamoto titled Bitcoin: A Peer-to-Peer Electronic Cash System[5] was posted to a cryptography mailing list.[26] Nakamoto implemented the bitcoin software as open source code and released it in January 2009 on SourceForge.[27][28][11] The identity of Nakamoto remains unknown.[10]
In January 2009, the bitcoin network came into existence after Satoshi Nakamoto mined the first ever block on the chain, known as the genesis block.[29][30] Embedded in the coinbase of this block was the following text:
The Times 03/