Cutting through the fog of blockchain and cryptocurrency hype, what is real and what is buzz in the world of blockchain? The technology has recently been divided into two main camps: Permissioned (private) blockchains, which primarily focus on bringing blockchain-based solutions to enterprises, and permissionless (public) blockchains, most notably Bitcoin, which aim to bring a fully decentralized cryptocurrency and distributed applications to the masses. Both camps have been hailed as world-altering breakthroughs, and accused of being worthless fads. Will the real blockchain please stand up?