Blockchain has been initially launched as an approach to payment transaction based on cryptography to provide an alternative mechanism for the trust between two transacting parties. This technology enables a collective bookkeeping system (ledger), which, by means of a mathematical function (has function), allows participants to reach an agreement on the approval of a transaction. The information concerning single transactions is gathered in 'blocks'. These blocks are reviewed and verified by the network and added in a chronological order on the computers of all participants of the network. A distributed ledger of verified transactions of a particular unit are then provided to the network.
As such, the traditional role played by financial institutions a trusted third party, able to mitigate the risk behind a transaction, is under scrutiny.
Bitcoin was the first digital currency and remains the largest until now. Furthermore, it represents one of the most famous applications of blockchain technology. Nowadays, blockchain is which range from real time payments between two parties (rapid settlement and without requiring a bank account) to transferring funds across currencies (micro payments, remittances), and digital assets (digitally stored records of ownership).