iCloud is a cloud storage and cloud computing service from Apple Inc. It allows users to store data such as documents, photos, and music on remote servers, which can then be accessed from any Apple device running macOS or iOS, as well as from PCs via iCloud for Windows. A subscription to iCloud typically provides features like automatic backup of devices, synchronization of data across devices, access to iCloud Drive for file storage, and the ability to share family storage. Additionally, iCloud offers services like Find My iPhone, iCloud Photo Library, and more.