Level one ISO-9660 is similar to an MS-DOS filesystem. Filenames are limited to eight single-case characters, a dot, and a three character extension. Filenames cannot contain special characters, (no hyphens, tildes, equals, or pluses). Only single case letters, numbers, and underscores. Directory names cannot have the three digit extension, just eight single-case characters.

All alphabetics are in UPPER case; some software maps this to lower case. Either the file name or the extension may be empty, but not both ("F." and ".E" are both legal file names).

There is a "File Version Number" which can range from 1-32767, and is separated from the extension by a semi-colon. The file version number is ignored on many systems.

Subdirectories are allowed to nest up to eight levels deep.

Level two ISO-9660 allows longer filenames, up to 32 characters. But many of the other restrictions still apply. Level two discs are not usable on some systems, particularly MS-DOS.

			Copyright ©1995 by ISOMEDIA, Inc. For Information, contact Ken Cheney