Apple’s cloud storage and syncing service is called iCloud.
Introduced in 2011, iCloud links Apple devices and services through a user’s Apple Account. It can synchronize information such as photos, notes, contacts, calendars, Safari data, device settings, and application data, so changes made on one device can appear on another. It also supports backups and services such as Find My.
A frequent confusion is between iCloud and iCloud Drive. iCloud is the broader cloud-services system, while iCloud Drive is the file-storage and file-synchronization component within it. iCloud Photos similarly focuses on keeping a user’s photo library available and synchronized across supported devices. Google Drive, Dropbox, and iDrive are separate companies’ services, not Apple products.
The service is built into Apple operating systems including iOS, iPadOS, macOS, watchOS, tvOS, and visionOS, and it can also be accessed through iCloud.com and a Windows client. Accounts include a limited amount of free storage, with paid iCloud+ tiers available for people who need more space or additional privacy-related features.