Also called UDF bridge, UDF/ISO is a hybrid filesystem utilizing UDF and ISO 9660. Developed because UDF wasn't supported by Windows until Microsoft shipped Windows 98, DVD providers were forced to use an interim format. Windows 95 OSR2 supports UDF Bridge, but earlier versions do not. As a result, to be compatible with Windows 95 versions previous to OSR2, DVD vendors had to provide UDF Bridge support along with their hardware.

DVD-ROM discs use the UDF Bridge format. (Note: Windows 95 was not designed to read UDF but can read ISO 9660). The UDF Bridge specification does not explicitly include the Joliet extensions for ISO 9660, which are needed for long filenames. Windows 98 and later MS operating systems read UDF so these systems have no problem with either UDF or long filenames. Burnworld