The Computers: Software: Operating Systems: x86: DOS: (DR-DOS DOS )

Digital Research DOS, known as DR-DOS, DOS compatible operating system that has been owned by many companies and known by several names over its history. It was originally developed by the makers of CP-M, one of the oldest operating systems for the x86 architecture. DR-DOS was later purchased by Novell and known as Novell DOS. Caldera Systems then bought Novell DOS and renamed it OpenDOS. Caldera then renamed the product back to DR-DOS. Caldera then spun off the company known as Lineo and transferred ownership of DR-DOS to Lineo. DR-DOS DOS x86 Operating Systems Software Computers.

DR-DOS ( DR DOS, without hyphen up to and including v6.0) is an operating system of the DOS family, written for IBM PC - compatible personal computers. (wikipedia)