A cryptocurrency is a digital or virtual currency designed to work as a medium of exchange. It uses cryptography to secure and verify transactions as well as to control the creation of new units of a particular cryptocurrency. Essentially, cryptocurrencies are limited entries in a database that no one can change unless specific conditions are fulfilled.
Bitcoin (BTC) is a digital currency, which is used and distributed electronically. Bitcoin is a decentralised peer-to-peer network. No single institution or person controls it. Bitcoins can't be printed and their amount is very limited - only 21 mln Bitcoins can ever be created. For a lot of people, the main advantage of Bitcoin is its independence from world governments.
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