Bitcoin is a cryptocurrency, a digital asset designed to work as a medium of exchange that uses cryptography to control its creation and management, rather than relying on central authorities. The presumed pseudonymous Satoshi Nakamoto integrated many existing ideas from the cypherpunk community when creating bitcoin. Over the course of bitcoin’s history, it has undergone rapid growth to become a significant currency both on and offline – from the mid 2010s, some businesses began accepting bitcoin in addition to traditional currencies.
On 18 August 2008, the domain name bitcoin.org was registered. Later that year, on 31 October, 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.This paper detailed methods of using a peer-to-peer network to generate what was described as “a system for electronic transactions without relying on trust”.On 3 January 2009, the bitcoin network came into existence with Satoshi Nakamoto mining the genesis block of bitcoin (block number 0), which had a reward of 50 bitcoins.Embedded in the coinbase of this block was the text:
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks.
The text refers to a headline in The Times published on 3 January 2009. This note has been interpreted as both a timestamp of the genesis date and a derisive comment on the instability caused by fractional-reserve banking.:18
The first open source bitcoin client was released on 9 January 2009, hosted at SourceForge.
One of the first supporters, adopters, contributors to bitcoin and receiver of the first bitcoin transaction was programmer Hal Finney. Finney downloaded the bitcoin software the day it was released, and received 10 bitcoins from Nakamoto in the world’s first bitcoin transaction on 12 January 2009.Other early supporters were Wei Dai, creator of bitcoin predecessor b-money, and Nick Szabo, creator of bitcoin predecessor bit gold.
In the early days, Nakamoto is estimated to have mined 1 million bitcoins. Before disappearing from any involvement in bitcoin, Nakamoto in a sense handed over the reins to developer Gavin Andresen, who then became the bitcoin lead developer at the Bitcoin Foundation, the ‘anarchic’ bitcoin community’s closest thing to an official public face.
The value of the first bitcoin transactions were negotiated by individuals on the bitcoin forum with one notable transaction of 10,000 BTC used to indirectly purchase two pizzas delivered by Papa John’s.
On 6 August 2010, a major vulnerability in the bitcoin protocol was spotted. Transactions weren’t properly verified before they were included in the transaction log or blockchain, which let users bypass bitcoin’s economic restrictions and create an indefinite number of bitcoins. On 15 August, the vulnerability was exploited; over 184 billion bitcoins were generated in a transaction, and sent to two addresses on the network. Within hours, the transaction was spotted and erased from the transaction log after the bug was fixed and the network forked to an updated version of the bitcoin protocol.This was the only major security flaw found and exploited in bitcoin’s history.