Stephen Downes

As Wikipedia notes, "a permissionless distributed database based on the bitcoin protocol that maintains a continuously growing list of transactional data records hardened against tampering and revision, even by operators of the data store's nodes." It might in time prove to be a significant invention. People have suggested the use of blockchains to recognize educational achievements. This article points to a couple of advances in the use of blockchains by financial institutions to maintain a common ledger system "to implement a fully decentralized payment system, in which copies of the ledger are shared between all participants, and a process is established by which users agree on changes to the ledger (that is, on which transactions are valid)."