Set up a Time Machine backup
Point macOS at an external disk once and it keeps hourly versions of everything by itself.
Published: · Source: Genius Manu
Time Machine is the backup system built into macOS. You configure it once and it runs unattended, keeping hourly versions for a day, daily ones for a month and weekly ones until the disk fills up — then it deletes the oldest.
Plug in an external drive and go to System Settings → General → Time Machine, then Add Backup Disk. Pick the drive and confirm. macOS will offer to erase it if the format is not suitable, so use an empty disk or one you only keep backups on.
What makes it worth the bother is restoring. You are not limited to putting the whole Mac back: open a folder, enter Time Machine, and step backwards through previous versions of that folder to recover a single file as it was last Tuesday.
A backup on a disk that lives next to the Mac protects you from a broken drive, not from theft or fire. If the data matters, add a copy somewhere else — iCloud, or a second disk you keep elsewhere.
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