If you’re not yet backing up your Mac, it’s probably because you didn’t realize how easy it is. All that’s required is a basic external drive and a few clicks to start the Mac’s built-in Time Machine feature. Of course, it’s possible to put extra time into creating a full-fledged backup scheme, but in this article, we’ll look at setting up a simple backup that protects against many possible problems with minimal effort.
For help selecting a drive, visit one of our stores or check out our article on the topic.
Once you’ve bought your drive, connected it to your Mac, and turned it on, you may be prompted to use the drive with Time Machine right away. If that happens, great! Select Encrypt Backup Disk if you’d like to password-protect your backups (make sure to keep track of that password!), and click Use as Backup Disk.
It’s a good idea to customize the name of your Time Machine drive so you can easily distinguish it. You can rename the drive before or after setting up Time Machine: Open a Finder window and from the sidebar at the left, under Devices, Control-click the drive. Choose Rename “drive name”. Type the new name and press Return.
If you didn’t set up Time Machine right away when you connected your drive, follow these steps to turn it on:
- Go to System Preferences > Time Machine, and click the Select Disk button.
- Select your new disk from the list.
- If you want to password-protect your backups, select Encrypt Backups. (If this checkbox is dimmed, hover over it to see more information. If no explanation appears, the disk doesn’t support encryption.) Should you select this checkbox? You have to decide which is more likely to be a problem—the wrong person poking around in your backup files or you losing the password and being unable to restore from your backup in an emergency.
- Click Use Disk.
- You may be asked whether it’s okay to reformat the disk. This will erase everything on the disk, so assuming that erasing is okay, go ahead and reformat.
- If you selected Encrypt Backups, enter the password twice, once in the Backup Password field and once in the Verify Password field. Also, give yourself a hint to help you remember it. (Be sure to record the password in a safe place where you can find it later!) Finally, click the Encrypt Disk button.
To confirm that Time Machine is making backups, look in the Time Machine preference pane. At the left, the Back Up Automatically checkbox should be selected. Also, the name of your backup disk should appear at the upper right, along with information about how a backup is beginning or when the last backup occurred. It’s fine to continue using your Mac normally while Time Machine makes a backup.
Keep the “Show Time Machine in menu bar” checkbox selected so you can check on your backups from the menu bar. Although Time Machine will warn you if something goes wrong, it’s still a good idea to check regularly to make sure backups are occurring. (Did you forget to turn on your backup drive?)
Time Machine makes versioned backups. What this means is that the first time Time Machine runs, it backs up all your files. The next time it runs, it backs up just the data that has changed, rather than replacing the first copy with a fresh copy. This approach is helpful for two reasons:
- Although the first backup will likely take several hours, subsequent backups should take much less time.
- You can retrieve a file from the past. If you deleted a portion of a file—or an entire file—months ago, you’ll now be able to get it back. Of course, this works only for deletions that were part of the Time Machine backup; you can’t go back to before you began making backups.
Time Machine runs once per hour. It keeps hourly backups from the past day, daily backups from the past week, and weekly backups until it runs out of space. If Time Machine runs out of space, it will cull older backups automatically.
You might wonder what happens if you’re using a laptop and can’t connect it to its backup drive for a while, such as during a trip. If space is available on the laptop’s startup drive, Time Machine will also make a day’s worth of hourly backups on the laptop’s startup drive—but you won’t see any mention of them in the Time Machine preference pane or menu bar menu. Time Machine moves those interim backups to the backup drive automatically once you reconnect it.
Time Machine should continue to squirrel away your backups indefinitely. If you experience buggy behavior that corrupts a file, or if you accidentally delete something important, you’ll be able to use Time Machine to restore an older version of the file so you don’t have to redo all your work from scratch. And, if your computer breaks or is stolen, you’ll be able to restore all your files to a new Mac.