If you've been playing along when people start discussing cloud computing (nothing to do with the sky, FYI), Mark Chu-Carroll breaks it down at his blog. "In the cloud, you don't have a specific server that you use. You have computing resources — that is, someone is renting you a certain about of computation on some collection of computers somewhere," he writes. "You don't know where the disks that store the data are. And you don't need to care."