Digital currencies or cryptocurrencies are secured by cryptography and generally used as a medium of exchange in a digital peer-to-peer (P2P) economic system. The use of cryptographic techniques is what ensures that these systems are completely immune to fraud and counterfeiting.
The first cryptocurrency to be created was Bitcoin, introduced by the pseudonymous developer Satoshi Nakamoto in 2009. Nakamoto’s goal was to create a new electronic payment system that would allow users to make digital financial transactions without the use of intermediaries, such as banks or government institutions.
Most cryptocurrency systems operate in a decentralized framework that is maintained collectively by a distributed network of computers. Each computer (or device) that joins the network is called a node and participates in the consensus validation of information. The information entered into the network is thus public, secure, unforgeable and unchangeable.