The virtual currency is about more than money – the real innovation is what people are doing with the technology it is based on
BITCOIN has been called many things, from the future of money to a drug dealer's dream and everything else in between. But beyond creating the web's first native currency, the true innovation of Bitcoin's mysterious designer, Satoshi Nakamoto, is its underlying technology, the "block chain". That fundamental concept is being used to transform Bitcoin – and could even replace it altogether.
So what is the block chain? It is a ledger of transactions that keeps Bitcoin secure and allows all users to agree on exactly who owns how many bitcoins. Each new block requires a record of recent transactions along with a string of letters and numbers, known as a hash, which is based on the previous block and produced using a cryptographic algorithm.
Miners, people who run the peer-to-peer Bitcoin software, randomly generate hashes, competing to produce one with a value below a certain target difficulty and thus complete a new block and receive a reward, currently 25 bitcoins. This difficulty means faking a transaction is impossible unless you have more computing power than everyone else on the Bitcoin network combined. Confused? Don't worry, ordinary Bitcoin users needn't know the details of how the block chain works, just as people with a credit card don't bother learning banking network jargon. But those who do understand the power of the block chain are realising how Nakamoto's technology for mass agreement can be adapted. "You can replace that agreement with all sorts of different things and now you have a really powerful building block for any kind of distributed system," says Jeremy Clark of Concordia University in Montreal, Canada.