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disk-operating system, often prefixed, as in MS-DOS and PC-DOS; a computer operating system


(computer science)


(operating system)
1. The common abbreviation for MS-DOS.

2. IBM's Disk Operating System.

3. Any disk operating system.


(1) See denial of service.

(2) (Disk Operating System) Any operating system that supports hard drives. See operating system.

(3) (Disk Operating System) A family of IBM mainframe operating systems (DOS, DOS/370, DOS/VS, DOS/VSE). As disk storage became accepted in the late 1960s, DOS started out as a variant of IBM's Tape Operating System (TOS); however, it was always the "junior partner" to OS/360 and its progeny. See DOS/VSE.

(4) (Disk Operating System)Pronounced "dahss." A single-user operating system from Microsoft for Intel x86 personal computers. It was the first operating system for IBM PCs and IBM-compatible PCs, and it remained the underlying control program for Windows 3.1, 95, 98 and ME. Subsequent versions of Windows incorporated all DOS functionality, and most DOS commands work the same in Windows. See cmd abc's.

The OS in the IBM PC was PC-DOS, and the OS used by all other PC makers was MS-DOS. Except for DOS 6, which contained different utilities, PC-DOS and MS-DOS commands and system functions were the same, and all PC-DOS and MS-DOS versions were commonly called "DOS." See DOS 6.

DOS Lives On
In various incarnations, DOS is still used in embedded systems, where a small OS footprint is required. Examples are Digital Research's DR-DOS, ROM-DOS from DataLight ( and the open source FreeDOS. See embedded system.
References in periodicals archive ?
The rest are either DOS (which can run on DOS or Windows 3.
If you can't justify the cost of a hardware changeover at this time, then choosing or staying with a DOS program may be the best answer - for now.
IQS Business System for DOS and Windows consists of 13 integrated software modules for ISO 9000 support, including one for calibration, documentation tasks, customer management, and supplier management.
A-Plus-Tax introduced its Windows version of the 1040 package this year, so now it has both a DOS and a Windows version.
GoSystem, as well as EasyGo--CLR's DOS product marketed to smaller firms--has extensive practice management tools.
One of the chief advantages of a DOS would be to merge science policy making and program implementation into a single structure.
IBM, which has kept pace with Microsoft through a competing version of DOS, caued PC-DOS, plans to keep the operating system alive.
The Power Macintosh 6100 DOS Compatible improves on the technology of the popular 68040-based Macintosh Quadra 610 DOS Compatible awarded "Best System" by Byte Magazine at Fall Comdex '93.
The process of installing Windows will be much more difficult than what we went through installing DOS.
In WordPerfect for DOS, select File, Text In, Spreadsheet and Import, and then select and enter the spreadsheet file's path and file name.
NASDAQ: APPL) today announced it has begun shipping the Macintosh Quadra 610 DOS Compatible, a full featured personal computer with MS-DOS- and Windows-compatibility.
Thus, when users want to network their computers to share data and application programs, special networking software has to be loaded on top of DOS.