What is blockchain technology?

Now in its 3rd edition, IBM’s Blockchain for Dummies has introduced blockchain to more than 68,000 readers. Blockchain defined: Blockchain is a shared, immutable ledger that facilitates the process of recording transactions and tracking assets in a business network.

Why is blockchain so secure?

This involves all nodes updating their version of the blockchain ledger to be identical. How these new blocks are created is key to why blockchain is considered highly secure. A majority of nodes must verify and confirm the legitimacy of the new data before a new block can be added to the ledger.

What is a bitcoin 'block chain'?

The network's 'nodes' — users running the bitcoin software on their computers — collectively check the integrity of other nodes to ensure that no one spends the same coins twice. All transactions are published on a shared public ledger, called the 'block chain.' ^ Gervais, Arthur; Karame, Ghassan O.; Capkun, Vedran; Capkun, Srdjan.

Are blockchain networks public or private?

Retrieved 7 July 2016. Blockchain networks can be either public or private. Public blockchains have many users and there are no controls over who can read, upload or delete the data and there are an unknown number of pseudonymous participants.