The growth in the amount of trading with cryptocurrencies and the recent appreciation of these virtual currencies in the financial markets demonstrate the potential that such technology has to attract attention in the global economy. The most striking feature of cryptocurrencies is the fact that they are created and managed without any state or banking intervention. The entire cryptocurrency market is underpinned by blockchain technology, a kind of "ledger" that records all transactions that have taken place since the creation of a particular currency. The system works like a "block chain" - hence the name - with each unit carrying information that cannot be tampered with. It is this technology, launched with Bitcoin 13 years ago, that prevents a cryptocurrency from being "copied" in the same way as other digital files, such as a photo or a text document. "Blockchain brings security to the market by ensuring that transactions are made with Bitcoins, and not a copy of the file"