List of disk operating systems called DOS

This is a list of disk operating systems in which the acronym DOS is used to form their names. Many of these are simply referred to as "DOS" within their respective communities.

MS-DOS / IBM PC DOS compatible systems

 * MS-DOS (since 1981), Microsoft operating system based on 86-DOS for x86-based personal computers
 * IBM PC DOS (since 1981), rebranded OEM version of MS-DOS sold by IBM. Identical or almost identical to MS-DOS until PC DOS version 6
 * DR-DOS (since 1988), MS-DOS-compatible operating system originally developed by Digital Research
 * ROM-DOS (1989), MS-DOS clone by Datalight
 * PTS-DOS (since 1993), MS-DOS clone developed in Russia by PhysTechSoft
 * FreeDOS (since 1998), open source MS-DOS clone

Other x86 disk operating systems with "DOS" in the name

 * 86-DOS (a.k.a. QDOS, created 1980), an operating system developed by Seattle Computer Products for its 8086-based S-100 computer kit, heavily inspired by CP/M
 * Concurrent DOS (a.k.a. CDOS, Concurrent PC DOS and CPCDOS) (since 1983), a CP/M-86 and MS-DOS 2.11 compatible multiuser, multitasking DOS, based on Concurrent CP/M-86 developed by Digital Research
 * DOS Plus (since 1985), a PC DOS and CP/M-86 compatible multitasking operating system for early x86-based personal computers, based on Concurrent PC DOS 4.1/5.0 by Digital Research
 * Multiuser DOS (a.k.a. MDOS), a PC DOS and CP/M-86 compatible multiuser multitasking operating system based on Concurrent DOS by Digital Research
 * NetWare PalmDOS, a successor of DR DOS 6.0 specifically tailored for early mobile and palmtop PCs by Novell
 * Novell DOS, a multitasking successor of DR DOS 6.0 by Novell
 * OpenDOS, a successor of Novell DOS by Caldera

Disk operating systems for the Atari 8-bit family

 * Atari DOS, from Atari, Inc.
 * DOS XL, from Optimized Systems Software
 * MyDOS
 * SmartDOS
 * SpartaDOS
 * SpartaDOS X
 * TOP-DOS
 * Turbo-DOS

Disk operating systems for other platforms

 * AmigaDOS, disk operating system portion of AmigaOS
 * AMSDOS, for Amstrad CPC compatibles
 * ANDOS, operating system for the Russian Electronika BK
 * Apple DOS, operating system for the Apple II series from late 1978 through early 1983
 * Apple ProDOS, name for both ProDOS 8 for the Apple II and ProDOS 16 for the Apple IIGS
 * Commodore DOS, for Commodore's 8-bit computers
 * Cromemco DOS (CDOS), a CP/M-like operating system
 * CSI-DOS, for the Soviet Elektronika BK computers
 * DOS (Diskette Operating System), a small OS for 16-bit Data General Nova computers, a cut-down version of their RDOS.
 * DEC BATCH-11/DOS-11, the first operating system to run on the PDP-11 minicomputer
 * Delta DOS, third party option from Premier Microsystems for the Dragon 32/64
 * DIP DOS, the operating system of the Atari Portfolio
 * DOS/360, 1966 IBM System/360 mainframe computer Disk Operating System
 * DragonDOS, for the Dragon 32/64
 * GEMDOS, one of the components of Atari TOS
 * IS-DOS, for Russian ZX Spectrum clones, developed in 1990 or 1991
 * IMDOS, for IMSAI 8080
 * MasterDOS, replacement DOS for the SAM Coupé
 * MDOS (Micropolis DOS) for S-100
 * MDOS, Myarc Disk Operating System for the Geneve 9640
 * MSX-DOS, a cross between MS-DOS 1.0 and CP/M developed by Microsoft for the MSX computer standard
 * NewDos/80, third-party option for the TRS-80
 * Oric DOS, for the Oric-1 home computer
 * PTDOS, for the 1970s Sol-20 from Processor Technology
 * SAMDOS, original DOS for the SAM Coupé
 * SDOS, for the SWTPC 6800 from the Southwest Technical Products Corporation
 * Sinclair QDOS, for the Sinclair QL
 * RDOS, a real-time operating system released in 1972 for the Data General Nova and Eclipse minicomputers
 * SK*DOS, for Motorola 68000-based systems
 * TR-DOS, for the ZX Spectrum
 * TRSDOS, for the Tandy TRS-80 line of 8-bit Zilog Z80 microcomputers
 * Xtal DOS for the Tatung Einstein