Like other iPods, the iPod shuffle can be used as a portable hard drive. The average person is more likely to use this feature with the shuffle than with other iPods, because unlike them, the iPod shuffle does not require the user to carry a connection cable, and it works equally well on Macs and PCs without drivers or reformatting.
By default, the ability to access the iPod shuffle as a hard drive is disabled. To enable it, enter the iPod Preferences page as we did above.

Here you’ll find an option entitled “Enable Disk Use.” When checked, iTunes will allow the iPod shuffle to appear in Windows Explorer (or the Mac OS’s Finder) as a detachable hard drive. The slider positioned below the checkbox instructs iTunes how much space to leave empty for data when filling the iPod via either Autofill or manual management. For example, in the photo above, we’ve reserved 128MB for non-audio use. Autofill will only fill the other 380-some Megabytes with music.
Why don’t I have the full drive capacity I paid for?
Using either Windows Explorer or the iTunes capacity bar at the bottom of the iPod shuffle page, you’ll notice that your iPod shuffle is reporting a slightly smaller total hard drive capacity than the number on the box. Don’t worry… this is completely normal for all storage media.
Contrary to popular belief, this anomaly is not caused by factory-installed programs, file system overhead, or swap space… it’s an unfortunate consequence of little more than math and marketing.
Hard drives are sold and marketed using decimal gigabytes. That is, a “GB” consists of 1,000,000,000 bytes. However, computers interpret gigabytes in binary. To a computer, 1 GB = 2^30 bytes, or 1,073,741,824 bytes.
The ratio of “actual” to “marketed” file size is the ratio of these two interpretations, or roughly 0.931.
Therefore, a 512MB iPod shuffle actually has 0.9313225*512MB, or about 476.8MB of space usable to a computer. A 1GB iPod shuffle will similarly report approximately 953.7MB.
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