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When you attach a storage disk to a Mac with the purpose of erasing or repartitioning it, you'll be presented with the option of selecting one of the three available partition maps: GUID Partition Map, Master Boot Record, and Apple Partition Map.
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With a working partition map, your USB will always show up in the Finder or Desktop. The partition on macOS could be APFS, MacOS Journaled, Encrypted MacOS Journaled or Case-Sensitive.Many users will remember that hard drive 'journaling,' now standard on Panther installations, was originally introduced in OS X 10.2 (Jaguar) as a 'Mac OS X Server-only' feature however, since.
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