Introduction To Windows, Basic DOS Commands Innovation
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Windows 2000 is a major release of the Windows NT operating system developed by Microsoft and oriented towards businesses. It was the direct successor to Windows NT 4.0, and was released to manufacturing on December 15, 1999, and was officially released to retail on February 17, 2000. It was Microsoft’s business operating system until the introduction of Windows XP Professional in 2001.
Windows 2000 introduced NTFS 3.0, Encrypting File System, as well as basic and dynamic disk storage. Support for people with disabilities was improved over Windows NT 4.0 with a number of new assistive technologies, and Microsoft increased support for different languages and locale information. The Windows 2000 Server family has additional features, most notably the introduction of Active Directory, which in the years following became a widely used directory service in business environments.
Four editions of Windows 2000 were released: Professional, Server, Advanced Server, and Datacenter Server; the latter was both released to manufacturing and launched months after the other editions. While each edition of Windows 2000 was targeted at a different market, they shared a core set of features, including many system utilities such as the Microsoft Management Console and standard system administration applications.
Microsoft marketed Windows 2000 as the most secure Windows version ever at the time; however, it became the target of a number of high-profile virus attacks such as Code Red and Nimda. For ten years after its release, it continued to receive patches for security vulnerabilities nearly every month until reaching the end of support on July 13, 2010, the same day which support ended for Windows XP SP2.
Windows 2000 and Windows 2000 Server were succeeded by Windows XP and Windows Server 2003, released in 2001 and 2003, respectively. Windows 2000’s successor, Windows XP, became the minimum supported OS for most Windows programs up until Windows 7 replaced it, and unofficial methods were made to run these programs on Windows 2000.
Windows 2000 is the final version of Windows which supports PC-98, i486 and SGI Visual Workstation 320 and 540, as well as Alpha, MIPS and PowerPC in alpha, beta, and release candidate versions. Its successor, Windows XP, requires a processor in any supported architecture (IA-32 for 32-bit CPUs and x86-64 and Itanium for 64-bit CPUs).
Windows 2000 is a continuation of the Microsoft Windows NT family of operating systems, replacing Windows NT 4.0. The original name for the operating system was Windows NT 5.0 and the prep beta builds were compiled between March to August 1997, these builds were identical to Windows NT 4.0. The first official beta was released in September 1997, followed by Beta 2 in August 1998. On October 27, 1998, Microsoft announced that the name of the final version of the operating system would be Windows 2000, a name which referred to its projected release date.Windows 2000 Beta 3 was released in May 1999. NT 5.0 Beta 1 was similar to NT 4.0, including a very similarly themed logo. NT 5.0 Beta 2 introduced a new ‘mini’ boot screen, and removed the ‘dark space’ theme in the logo. The NT 5.0 betas had very long startup and shutdown sounds, though these were changed in the early Windows 2000 beta, but during Beta 3, a new piano-made startup and shutdown sounds were made, featured in the final version as well as in Windows Me. The new login prompt from the final version made its first appearance in Beta 3 build 1946 (the first build of Beta 3). The new, updated icons (for My Computer, Recycle Bin etc.) first appeared in Beta 3 build 1964. The Windows 2000 boot screen in the final version first appeared in Beta 3 build 1983. Windows 2000 did not have an actual code name because, according to Dave Thompson of Windows NT team, “Jim All chin didn’t like code names”.
MS-DOS (/ˌɛmˌɛsˈdɒs/ em-es-DOSS; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few operating systems attempting to be compatible with MS-DOS, are sometimes referred to as “DOS” (which is also the generic acronym for disk operating system). MS-DOS was the main operating system for IBM PC compatibles during the 1980s, from which point it was gradually superseded by operating systems offering a graphical user interface (GUI), in various generations of the graphical Microsoft Windows operating system.
IBM licensed and re-released it in 1981 as PC DOS 1.0 for use in its PCs. Although MS-DOS and PC DOS were initially developed in parallel by Microsoft and IBM, the two products diverged after twelve years, in 1993, with recognizable differences in compatibility, syntax, and capabilities.
Beginning in 1988 with DR-DOS, several competing products were released for the x86 platform, and MS-DOS went through eight versions, until development ceased in 2000. Initially, MS-DOS was targeted at Intel 8086 processors running on computer hardware using floppy disks to store and access not only the operating system, but application software and user data as well. Progressive version releases delivered support for other mass storage media in ever greater sizes and formats, along with added feature support for newer processors and rapidly evolving computer architectures. Ultimately, it was the key product in Microsoft’s development from a programming language company to a diverse software development firm, providing the company with essential revenue and marketing resources. It was also the underlying basic operating system on which early versions of Windows ran as a GUI.
MS-DOS was a renamed form of 86-DOS – owned by Seattle Computer Products, written by Tim Paterson. Development of 86-DOS took only six weeks, as it was basically a clone of Digital Research’s CP/M (for 8080/Z80 processors), ported to run on 8086 processors and with two notable differences compared to CP/M: an improved disk sector buffering logic, and the introduction of FAT12 instead of the CP/M file system. This first version was shipped in August 1980. Microsoft, which needed an operating system for the IBM Personal Computer, hired Tim Paterson in May 1981 and bought 86-DOS 1.10 for US$75,000 in July of the same year. Microsoft kept the version number, but renamed it MS-DOS. They also licensed MS-DOS 1.10/1.14 to IBM, which, in August 1981, offered it as PC DOS 1.0 as one of three operating systems for the IBM 5150 or the IBM PC.
Within a year, Microsoft licensed MS-DOS to over 70 other companies. It was designed to be an OS that could run on any 8086-family computer. Each computer would have its own distinct hardware and its own version of MS-DOS, similar to the situation that existed for CP/M, and with MS-DOS emulating the same solution as CP/M to adapt for different hardware platforms. To this end, MS-DOS was designed with a modular structure with internal device drivers (the DOS BIOS), minimally for primary disk drives and the console, integrated with the kernel and loaded by the boot loader, and installable device drivers for other devices loaded and integrated at boot time. The OEM would use a development kit provided by Microsoft to build a version of MS-DOS with their basic I/O drivers and a standard Microsoft kernel, which they would typically supply on disk to end users along with the hardware. Thus, there were many different versions of “MS-DOS” for different hardware, and there is a major distinction between an IBM-compatible (or ISA) machine and an MS-DOS [compatible] machine. Some machines, like the Tandy 2000, were MS-DOS compatible but not IBM-compatible, so they could run software written exclusively for MS-DOS without dependence on the peripheral hardware of the IBM PC architecture.
This design would have worked well for compatibility, if application programs had only used MS-DOS services to perform device I/O, and indeed the same design philosophy is embodied in Windows NT (see Hardware Abstraction Layer). However, in MS-DOS’s early days, the greater speed attainable by programs through direct control of hardware was of particular importance, especially for games, which often pushed the limits of their contemporary hardware. Very soon an IBM-compatible architecture became the goal, and before long all 8086-family computers closely emulated IBM’s hardware, and only a single version of MS-DOS for a fixed hardware platform was needed for the market. This version is the version of MS-DOS that is discussed here, as the dozens of other OEM versions of “MS-DOS” were only relevant to the systems they were designed for, and in any case were very similar in function and capability to some standard version for the IBM PC—often the same-numbered version, but not always, since some OEMs used their own proprietary version numbering schemes (e.g. labeling later releases of MS-DOS 1.x as 2.0 or vice versa)—with a few notable exceptions.
Microsoft omitted multi-user support from MS-DOS because Microsoft’s Unix-based operating system, Xenix, was fully multi-user. The company planned, over time, to improve MS-DOS so it would be almost indistinguishable from single-user Xenix, or XEDOS, which would also run on the Motorola 68000, Zilog Z8000, and the LSI-11; they would be upwardly compatible with Xenix, which Byte in 1983 described as “the multi-user MS-DOS of the future”. Microsoft advertised MS-DOS and Xenix together, listing the shared features of its “single-user OS” and “the multi-user, multi-tasking, UNIX-derived operating system”, and promising easy porting between them. After the breakup of the Bell System, however, AT&T Computer Systems started selling UNIX System V. Believing that it could not compete with AT&T in the Unix market, Microsoft abandoned Xenix, and in 1987 transferred ownership of Xenix to the Santa Cruz Operation (SCO).
On March 25, 2014, Microsoft made the code to SCP MS-DOS 1.25 and a mixture of Altos MS-DOS 2.11 and TeleVideo PC DOS 2.11 available to the public under the Microsoft Research License Agreement, which makes the code source-available, but not open source as defined by Open Source Initiative or Free Software Foundation standards. Microsoft would later re-license the code under the MIT License on September 28, 2018, making these versions free software.
As an April Fool’s Day joke in 2015, Microsoft Mobile launched a Windows Phone application called MS-DOS Mobile which was presented as a new mobile operating system and worked similar to MS-DOS.
COMMAND.COM is the default command-line interpreter for MS-DOS, Windows 95, Windows 98 and Windows Me. In the case of DOS, it is the default user interface as well. It has an additional role as the usual first program run after boot (init process), hence being responsible for setting up the system by running the AUTOEXEC.BAT configuration file, and being the ancestor of all processes.
COMMAND.COM’s successor on OS/2 and Windows NT systems is cmd.exe, although COMMAND.COM is available in virtual DOS machines on IA-32 versions of those operating systems as well.
The COMMAND.COM filename was also used by Disk Control Program (DCP), an MS-DOS derivative by the former East German VEB Robotron.
The compatible command processor under FreeDOS is sometimes also named FreeCom.
COMMAND.COM is a DOS program. Programs launched from COMMAND.COM are DOS programs that use the DOS API to communicate with the disk operating system.
s a shell, COMMAND.COM has two distinct modes of operation. The first is interactive mode, in which the user types commands which are then executed immediately. The second is batch mode, which executes a predefined sequence of commands stored as a text file with the .BAT extension.
This article presents a list of commands used by DOS operating systems, especially as used on x86-based IBM PC compatibles (PCs). Other DOS operating systems are not part of the scope of this list.
In DOS, many standard system commands were provided for common tasks such as listing files on a disk or moving files. Some commands were built into the command interpreter, others existed as external commands on disk. Over the several generations of DOS, commands were added for the additional functions of the operating system. In the current Microsoft Windows operating system, a text-mode command prompt window, cmd.exe, can still be used.
The command interpreter for DOS runs when no application programs are running. When an application exits, if the transient portion of the command interpreter in memory was overwritten, DOS will reload it from disk. Some commands are internal—built into COMMAND.COM; others are external commands stored on disk. When the user types a line of text at the operating system command prompt, COMMAND.COM will parse the line and attempt to match a command name to a built-in command or to the name of an executable program file or batch file on disk. If no match is found, an error message is printed, and the command prompt is refreshed.
External commands were too large to keep in the command processor, or were less frequently used. Such utility programs would be stored on disk and loaded just like regular application programs but were distributed with the operating system. Copies of these utility command programs had to be on an accessible disk, either on the current drive or on the command path set in the command interpreter.
In the list below, commands that can accept more than one file name, or a filename including wildcards (* and ?), are said to accept a filespec (file specification) parameter. Commands that can accept only a single file name are said to accept a filename parameter. Additionally, command line switches, or other parameter strings, can be supplied on the command line. Spaces and symbols such as a “/” or a “-” may be used to allow the command processor to parse the command line into filenames, file specifications, and other options.
The command interpreter preserves the case of whatever parameters are passed to commands, but the command names themselves and file names are case-insensitive.
Many commands are the same across many DOS systems, but some differ in command syntax or name.