When the digital currency Bitcoin came to life in January 2009, it was noticed by almost no one apart from the handful of programmers who followed cryptography discussion groups. Its origins were shadowy: it had been conceived the previous year by a still-mysterious person or group known only by the alias Satoshi Nakamoto1. And its purpose seemed quixotic: Bitcoin was to be a ‘cryptocurrency’, in which strong encryption algorithms were exploited in a new way to secure transactions. Users’ identities would be shielded by pseudonyms. Records would be completely decentralized. And no one would be in charge — not governments, not banks, not even Nakamoto.
Yet the idea caught on. Today, there are some 14.6 million Bitcoin units in circulation. Called bitcoins with a lowercase ‘b’, they have a collective market value of around US$3.4 billion. Some of this growth is attributable to criminals taking advantage of the anonymity for drug trafficking and worse. But the system is also drawing interest from financial institutions such as JP Morgan Chase, which think it could streamline their internal payment processing and cut international transaction costs. It has inspired the creation of some 700 other cryptocurrencies. And on