[neuronexmachina]

Blockchains (e.g. bitcoin) and block lattice (e.g. RaiBlocks) are two approaches to implementing distributed ledgers. A distributed ledger is a type of distributed database. This article from last year I think sums up nicely the distinction between a distributed ledger and a distributed database.

https://medium.com/@sbmeunier/blockchain-technology-a-very-s...

> Distributed Ledgers (DL) are DDBMS that leverage cryptography to provide a decentralized multi-version concurrency control mechanism and to maintain consensus about the existence and status of shared facts in trustless environments (i.e. when the participants hosting the shared database are independent actors that don’t trust each other). Consensus is not a unique feature of DL per se: other distributed databases also use consensus algorithms such as Paxos or Raft. Same for immutability: immutable databases exist outside DL (Google HDFS, Zebra, CouchDB, Datomic, etc.). The two differentiators of DL in my opinion: (a) the control of the read/write access is truly decentralized and not logically centralized as for other distributed databases, and corollary (b) the ability to secure transactions in competing environments, without trusted third parties.