Universal Disk Format (UDF) is a file system format used on optical, recordable discs such as CD-R, CD-RW and various DVD formats. For example DVD-Video discs are written in UDF. UDF also enables users to use a recordable, re-writable media like a floppy disc. Mount Rainier is an extension to the UDF specification which enables more flexible use of re-writable media in a plug-and-play manner.
Compared to ISO 9660, the most common file system used on optical media, UDF offers many improvements and enhancements. The most notable differences are: support for larger files and disk sizes, and operating system specific file attributes.
