I formatted an external hard drive to my macbook to use for time machine. I now want to "unformat" it so I can use it as a transfer device (large flash drive). How do I do it??

1. Connect the External HD and open Disk Utility in your Utilities Folder.

2. Highlight the external HD in the list of drives and select the Partition tab.

3. Under Partition Layout select 1 Partition and click on the Options... button.

4. Select Master Boot Record in the drop down window and click OK.

5. Set the Format: to MS-DOS (FAT), name it and click the Apply button.

6. Click the Partition button.