Flavio Junqueira is the author of Zookeeper: Distributed Process Coordination. Flavio and Jeff Meyerson begin by defining ZooKeeper and talking about what ZooKeeper is and isn't. ZooKeeper can be thought of as a patch against certain fallacies of distributed computing: that the network is secure, has zero latency, has infinite bandwidth, and so on. With ZooKeeper, a programmer can be insulated from these problems or at least have a tool to better manage them. More concisely, ZooKeeper is a coordination kernel. It's a set of primitives that abstracts away coordination, leader election, and other troublesome aspects of maintaining a distributed system. Flavio also discusses scaling ZooKeeper, the CAP theorem, and contrasting distributed tools such as Chubby.