File storage and transfer

All iPods except for the touch can function in "disk mode" as mass storage devices to store data files[9]. If the iPod is formatted on a Mac OS X computer it uses the HFS+ file system format, which allows it to serve as a boot disk for a Mac computer.[10] If it is formatted on Windows, the FAT32 format is used. With the advent of the Windows-compatible iPod, iPod's default file system switched from HFS+ to FAT32, although it can be reformatted to either filesystem (excluding the iPod shuffle which is strictly FAT32). Generally, if a new iPod (excluding the iPod shuffle) is initially plugged into a computer running Windows, it will be formatted with FAT32, and if initially plugged into a Mac running Mac OS X it will be formatted with HFS+.

Unlike many other MP3 players, simply copying audio or video files to the drive with a typical file management application will not allow iPod to properly access them. The user must use software that has been specifically designed to transfer media files to iPods, so that the files are playable and viewable. Aside from iTunes, several alternative third-party applications are available on a number of different platforms.

iTunes 7 and above can transfer purchased media of the iTunes Store from an iPod to a computer, provided that the DRM media is transferred to any of the five computers allowed for authorization with DRM media.

Media files are stored on the iPod in a hidden folder, together with a proprietary database file. The hidden content can be accessed on the host operating system by enabling hidden files to be shown. The audio can then be recovered manually by dragging the files or folders onto the iTunes Library or by using third-party software.