As you may already know when setting up your iCloud account, Apple offers you 5Gb of storage totally free for your files, data, backup copies and email only in the case of using the following email domains, @ mac.com, @ me.com or @ icloud.com, on any of your devices.
This space can be expanded to 10Gb, 20Gb or 50Gb but paying a fee of € 16, € 32 or € 80 per year respectively that will be added to the already 5 Gb free.
To check our configuration on Mac, we just have to go to the system preferences and we will go to the iCloud icon to access the options that iCloud gives us to store our contacts, calendars, reminders, Safari, notes and Photos in Streaming that also do not occupy any of the free 5 Gb, something that is very welcome and makes the synchronization between devices be much simpler.
But it is not all so perfect and it is that the Photos in Streaming althoughe do not take up space of the 5 Gb Storage will only be available in "the cloud" for a period of 30 days until we save them locally, otherwise they will be eliminated and apart they will not be available via the web through the icloud.com.
Backups on Mac are not possible completely just as it happens in iOS devices like the iPhone or iPad, since only contacts, calendars, notes, documents and data will be saved as I said ...
But to carry out a complete backup and be totally protected against system failures in relation to the software the best will use Time Machine for this purpose from my point of view.
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