Mac OS Extended Format (or HFS Plus)

With Mac OS 8.1, Apple introduced Mac OS Extended Format, or HFS Plus. Designed for high-capacity hard disks, HFS Plus decreases the minimum size of an allocation block, thus decreasing the amount of disk space that small files require. The net effect: You can store more information on disk.

Tip

To use HFS Plus, the computer to which the hard disk is directly connected must have Mac OS 8.1 or later installed.

Tip

Do not use HFS Plus to format removable media (Zip, Jaz, etc.) that is shared with computers running Mac OS versions prior to 8.1. Those computers will not be able to read individual files on HFS Plus disks.

Tip

HFS Plus works best with hard disks that are 1 GB or larger in capacity.

Tip

The "old" ...

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