Marco Streng is a miner, though he does not carry a pick around his base in south-western Iceland. Instead, he keeps tens of thousands of computers running 24 hours a day in fierce competition with others across the globe to earn bitcoins.
In the world of the web-based digital currency, it is not central banks that add new money to the system, but rather computers like Streng’s which are awarded fresh bitcoins in return for processing blocks of the latest bitcoin transactions.
Bitcoin can be used to send money instantly around the world, using individual bitcoin addresses, free of charge with no need for third party checks, and is accepted by several major online retailers.
The work Streng’s computers and others do serves two purposes: they record and verify the roughly 225,000 daily bitcoin transactions and—because they earn new bitcoins for the work they do—steadily increase the currency in circulation, currently worth around $10 billion.
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The process has come to be known as “mining” because it is slow and intensive, reaping a gradual reward in the same way that minerals such as gold are mined from