Blockchain is the best known distributed ledger technology. A ledger keeps a final and definitive record of transactions. Transactions on a blockchain are not centrally stored but instead identical copies of all transactions are kept on decentralised ledgers at the same time. These data are moreover encrypted. Records, once stored, cannot therefore be tampered with on one of these ledgers without leaving a track. This is an essential difference to databases that are managed by a central operator.
The decentralised nature of record keeping in combination with encryption of data provides users trust, traceability and security for exchanging their data and/or assets. There is high potential for blockchain to be used in many different areas such as in financial services, supply chains, energy, healthcare and the public sector.