Bitcoin is a peer-to-peer payment system and digital currency introduced as open source software in 2009 by pseudonymous developer Satoshi Nakamoto. Bitcoin is the first cryptocurrency, so-called because it uses cryptography.[6] When paying with Bitcoin, no exchange of digital notes or tokens takes place between payer and payee. Instead, the buyer requests an update to a public transaction log. All transactions are verified, timestamped, and recorded into this shared public database called the block chain.[7] The operators of the computers that do such payment processing work are known as "miners" and rewarded with transaction fees as well as newly minted bitcoins.[8]
Bitcoin has been a subject of scrutiny due to ties with illicit activity. In 2013 the FBI shut down the Silk Road online black market and seized US$28.5 million worth of bitcoin.[9] However, the United States is currently considered to be Bitcoin friendly compared to other governments[citation needed]. In China, new rules mean bitcoins cannot be exchanged for local currency,[10] and the European Banking Authority has warned that Bitcoin lacks consumer protections.[11] Theft of bitcoins can and does occur.[12] Generating and storing keys offline mitigates such risks, however.[13]
Commercial use of Bitcoin, illicit or otherwise, is currently small compared to its use by speculators, which has fueled price volatility.[14] Bitcoin as a form of payment for products and services has seen growth, however, and merchants have an incentive to accept the currency because transaction fees are lower than the 2-3% typically imposed by credit card processors.[15] Notable vendors accepting bitcoin include OkCupid, Reddit, and Virgin Galactic.[16]
"Bitcoin", capitalized, refers to the protocol and transaction network but "bitcoins", lowercase, refers to the currency itself