Backing up to an external drive protects your data when disaster strikes.
Mac OS X includes a backup program called Time Machine that can backup your data on an hourly basis. It’s designed to work with an external hard drive so that if something happens to your computer or its internal drive, your data will be protected. Most external drives are formatted for Windows; your Mac can read and write to these drives, but they can’t be used with Time Machine until you reformat them. Make sure to copy any data on the drive before reformatting since this will erase the drive.
1. Open “Finder” and go to the “Applications” folder, then the “Utilities” folder.
2. Plug your external hard drive in and run the “Disk Utility” program.
3. Click the icon for the external drive on the left side of the window and then click the “Partition” tab. If the format is listed as “Mac OS Extended (Journaled)” close Disk Utility and continue to Step 7.
4. Click the menu under “Volume Scheme” and select “1 Partition.”
5. Click the menu next to “Format” and select “Mac OS Extended (Journaled),” then click “Apply” to format the drive.
6. Close the Disk Utility program.
7. Click the “Apple” menu and then “System Preferences.”
8. Click “Time Machine” in the “System” section.
9. Click “Change Disk” and select the external hard drive. Time Machine is now configured and will perform automatic backups.