iCloud is a type of cloud storage and cloud computing service from Apple Inc.
The iCloud is a storage and cloud computing service offered by Apple Inc. which was first announced on June 6, 2011 at the Apple Worldwide Developers Conference (WWDC).
Among other features comes the ability to keep your iDevices in sync and storing photos taken with your iPhone or iPad.
While questions relating to products by Apple Inc. aren't necessarily off-topic on SuperUser, AskDifferent is specifically focused on these types of questions. A question regarding iCloud might attract more attention over there.