Blockchain appeared in 2008 alongside Bitcoin, and while Bitcoin took a great deal of the initial attention as a disruptive currency, professional services including accountancy and banking are now seriously investigating what Blockchain can do for them.

Essentially, Blockchain is a digital ledger of transactions. Instead of everyone keeping their own records, though, it is mutual, with everyone involved sharing the same ledger of transactions. It operates by consensus, so if all parties agree that a transaction is legitimate, it is then added to the chain and cannot be altered after the fact. That is, at least, the theory.