User Guide

86 Creating a DVD
Multiple File Systems on a Disc
All DVD discs contain at least two file systems: the universal disc format (UDF)
file system and the ISO 9660 file system. Among other things, these file systems
define how a DVD-ROM file name appears when viewed on a computer.
The UDF file system allows file names of up to 255 Unicode characters, which can
include accented characters and Asian characters. All modern computer operating
systems read the UDF file system. Older operating systems, such as Windows 95,
read the ISO 9660 file system, which limits file names to 8+3 characters (like MS-
DOS file names) and allows only numeric and uppercase ASCII characters plus the
hyphen to be used. Also, under ISO 9660 folders can be nested only eight levels
deep. If you want the DVD-ROM files to be usable on older systems, you must
limit the file names to 8+3 characters.
To get around the limitations of ISO 9660, you can include the Joliet file system
when you create a disc. This allows up to 110 Unicode characters in file names
and unlimited nested folders, but it works only under Windows 95. It also takes
up some disc space. If the project contains no DVD-ROM files, you should turn
off the
Joliet option when you create the disc.
DVDit! also lets you use a version of ISO 9660 that allows file names up to 30
characters long, but this is incompatible with PCs running MS-DOS. If you want
the DVD-ROM files to be usable under MS-DOS, you should turn off the
Use
long file names option when you create the disc.
Temporary Storage
By default, DVDit! creates a temporary DVD volume before writing the files to the
DVD disc, DVD volume or DVD master. If your PC has limited disk space, you
may prefer to turn off this feature; in this case, DVDit! writes the files directly to
the output medium.