A blockchain is “an interesting and new kind of organism” Buterin says after we have slid across floorboards through the open-plan living room to a wooden dining table. That is something of an understatement, I think. Simply put, a blockchain is a ledger stored across thousands of computers. Spreading the record out this way, and securing it with Byzantine mathematics called cryptography, makes it harder to tamper with than traditional information hoards. Centralised data troves, such as your brain, are liable to lose things — and, as Equifax found via the hacking of its customer data files, are vulnerable to attack. By contrast, blockchain ledgers are open for all to read and not controlled by a single entity.

https://www.ft.com/content/b09d004e-4197-11e8-803a-295c97e6fd0b