iCloud Deconstructed

Apple's iCloud service is unique in its convention as a "cloud service".

Generally speaking, "cloud services" are external virtual pieces of real estate where you can stash your data. They offer different sorts of tools and processes that allow you to access and use that data in ways that meet various needs, so you have a several that you can choose from to store and manipulate your data.

iCloud in the Apple realm serves an entirely different purpose - one that is designed to compliment and support the Applesphere of our iPhones, iPads, and Macs. So, in this environment, the cloud service being offered is primarily a piece of virtual real estate that acts as a "hub" to bring all of your devices and Macs together. So, it is not (with the exception of the iOS Backup function), an archival storage cloud service, but rather it is a syncing/sharing cloud service.

You share your data between your devices and computers by turning on the same options, and signing into the same iCloud account on each computer or device that you want to sync/share with. The data can be accessed via apps on your devices and computers, or via apps on iCloud.com.

iCloud has several functions, all of which you can choose to use or not. The various services and features available under the iCloud umbrella are:

iCloud Sync (does not use your iCloud Storage): The iCloud Sync function allows you to select whether you want to sync your Contacts, Calendars, Notes, Reminders, etc. between devices.

- These options are set up on your iOS device under Settings>your name>iCloud, and under "Apps Using iCloud" turn on the options you want to sync

- These options are set up on your Mac under >System Preferences>iCloud

iOS Device iCloud Backups: You can back up the contents of your devices automatically or manually so that they can be used to restore or set up a new device.

- Automatic Backups can be set up by going to Settings>your name>iCloud>Backup, and turn on the iCloud Backup option. This will cause your iOS device to back up when your device is attached to a power source, has Wifi, and is on the Lock screen. It will do this up to once a day

- Manual Backups can be executed at any time by going to Settings>your name>iCloud>Backup, and tap on the "Backup Now" option at the bottom of the display

iCloud Photo Library: You can use iCloud syncing/sharing services to upload all of your photos to a common library that can be accessed and shared by all of your devices and computers.

- This option is set up on your iOS device under Settings>Photos & Camera>iCloud Photo Library

- This option is set up on your Mac under Photos>Preferences>iCloud>check iCloud Photo Library

iCloud Photo Library FAQ - Apple Support

iCloud Photo Library Help - Apple Support

iCloud Drive: You can upload files to iCloud Drive so that they can be shared among all of your devices and computers. An additional option here is to set up your Macs to use iCloud Drive to share your Desktop and Document folders between all of them. If you choose this option, then they all would have mirror desktops, and would also all have all documents between them.

- You can turn on iCloud Drive on your iOS device by going to Settings>your name>iCloud>turn on the iCloud Drive option (iCloud Drive folders can be found in the "Files" app in iOS 11 and up, and in the "iCloud Drive" app in earlier iOS versions

- You can turn on iCloud Drive on your Mac by going to >System Preferences>iCloud>and check iCloud Drive. If you choose to share Documents and Desktops between Macs, you would then click on the Options next to iCloud Drive, and check the "Desktop & Documents" option

iCloud Drive FAQ - Apple Support

Add your Desktop and Documents files to iCloud Drive - Apple Support

iCloud: Use iCloud Drive on iCloud.com

In addition to all of the above iCloud features which do take up your allotted iCloud Storage (with the noted exception), the following services are also available, and they do not take up any of your iCloud Storage:

Photo Stream - shares with all devices, and keeps up to 30 days or 1000 photos (whichever comes first)

iCloud Photo Sharing (iCloud Photo Sharing - Apple Support)

iCloud Music Library (for Apple Music and iTunes Match)

You can select any or all of these features, and tailor which ones you use individually by device. There is no overall dictate as to how you use iCloud and its various services.

Note: One other "Cloud" reference in the Apple lexicon is "iTunes in the Cloud". This particular phrase refers to your iTunes purchases that you do not have downloaded to a particular device, but which is represented on that device with a little cloud next to it, indicating that you can download it from iTunes in the Cloud where it is being saved for you.