DOS.MASTER (also: DOS Master) is a program for Apple II computers which allows Apple DOS 3.3 programs to be placed on a hard drive or 3½" floppy disk and run from ProDOS. It was written by Glen Bredon (1932 - 2000) as a commercial program during the late 1980s where it experienced widespread success; it was released into the public domain by his family after the author's death.