SD cards are commonly used in digital cameras and other portable devices to externally store data that can then be accessed on computers. With storage capacities ranging from under 1GB to more than 64GB, they can also be used as portable storage drives. Although your SD card should work out of the box with your Mac computer, you may wish to reformat it. With Apple's built-in Disk Utility program, you can format your SD card to use either the FAT or Mac Extended Journal file systems.
Insert your SD card into your Mac computer's SD card reader. If your Mac does not have a built-in SD card reader, you can purchase a card reader that plugs into the USB or Firewire port on your Mac.
Click the "Go" button in the Mac menu and then click "Applications."
Double-click the "Utilities" folder within "Applications." Double-click the "Disk Utility" app icon to launch the application.
Select your SD card on the left side of the "Disk Utility" program. Click the "Erase" tab.
Click the drop-down box next to "Volume Format" and select the type of formatting for the SD card. Select "FAT" if you wish to access the SD card on both Macs and Windows-based computers. If you only want to use the card with your Mac, select "Mac OS Extended."
Type in a name for the SD card next to "Name." Click the "Erase" button to begin formatting the SD card. Wait for the "Format Complete" box to appear before disconnecting the SD card from your Mac.
- Formatting the SD card erases all data on the card, so be sure to back up any data that you want to save.
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