The 30-second definition.
Though it sounds like a series of defensive maneuvers ripped out of an NFL playbook, the blockchain is actually a way to structure data, and the foundation of cryptocurrencies like Bitcoin. This coding breakthrough—which consists of concatenated blocks of transactions—allows competitors to share a digital ledger across a network of computers without need for a central authority. No single party has the power to tamper with the records: the math keeps everyone honest. Forty of the world’s top financial firms are experimenting with the tech.
Example of blockchain in a sentence:
“Bitcoin the currency, I think, is going to go nowhere … the blockchain is a technology which we’ve been studying and yes it’s real.” —Jamie Dimon on CNBC
For more on the blockchain, watch this Fortune video:
A version of this article appears in the June 1, 2016 issue of Fortune with the headline “Word Check: Blockchain.”