How can I tell when my mac was last backed up to icloud?
How can I back up to icloud now?
iMac, macOS 10.13
Question marked as
Top-ranking reply
Apple offers iCloud Backup for iPhones and iPads but not for Mac computers.
It is possible to sync data from a Mac to iCloud if you turn on those options (e.g., iCloud Photos, iCloud Drive including the Desktop & Documents option). Syncing has some of the benefits of a backup (and the benefit of being offsite) but is not the same as a backup. Major differences include the fact that not everything on your Mac can be synced and the fact that if you delete something, accidentally or otherwise, there is only a limited time period (30 days in most cases) during which it can be recovered.
Syncing is done dynamically as data changes. For example adding a new contact will result in Contacts syncing (if that option is turned on) but will not cause Photos to sync (if that option is turned on).
More information on syncing in:
Set up and use iCloud Photos - Apple Support
and