Multi-user software is

computer software Software consists of computer programs that instruct the Execution (computing), execution of a computer. Software also includes design documents and specifications. The history of software is closely tied to the development of digital comput ...

that allows access by multiple

user Ancient Egyptian roles * User (ancient Egyptian official), an ancient Egyptian nomarch (governor) of the Eighth Dynasty * Useramen, an ancient Egyptian vizier also called "User" Other uses * User (computing), a person (or software) using an ...

s of a

computer A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...

Time-sharing In computing, time-sharing is the Concurrency (computer science), concurrent sharing of a computing resource among many tasks or users by giving each Process (computing), task or User (computing), user a small slice of CPU time, processing time. ...

systems are multi-user systems. Most

batch processing Computerized batch processing is a method of running software programs called jobs in batches automatically. While users are required to submit the jobs, no other interaction by the user is required to process the batch. Batches may automatically ...

systems for

mainframe computer A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterprise ...

s may also be considered "multi-user", to avoid leaving the

CPU A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary processor in a given computer. Its electronic circuitry executes instructions of a computer program, such as arithmetic, log ...

idle while it waits for I/O operations to complete. However, the term " multitasking" is more common in this context. An example is a

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

Unix-like A Unix-like (sometimes referred to as UN*X, *nix or *NIX) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Uni ...

system where multiple remote users have access (such as via a

serial port A serial port is a serial communication Interface (computing), interface through which information transfers in or out sequentially one bit at a time. This is in contrast to a parallel port, which communicates multiple bits simultaneously in Pa ...

Secure Shell The Secure Shell Protocol (SSH Protocol) is a cryptographic network protocol for operating network services securely over an unsecured network. Its most notable applications are remote login and command-line execution. SSH was designed for ...

) to the

Unix shell A Unix shell is a Command-line_interface#Command-line_interpreter, command-line interpreter or shell (computing), shell that provides a command line user interface for Unix-like operating systems. The shell is both an interactive command languag ...

prompt at the same time. Another example uses multiple

X Window The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems. X originated as part of Project Athena at Massachusetts Institute of Technology (MIT) in 1984. The X protocol has been a ...

sessions spread across multiple terminals powered by a single machine – this is an example of the use of

thin client In computer networking, a thin client, sometimes called slim client or lean client, is a simple (low-Computer performance, performance) computer that has been Program optimization, optimized for Remote desktop, establishing a remote connectio ...

. Similar functions were also available in a variety of non-Unix-like operating systems, such as

Multics Multics ("MULTiplexed Information and Computing Service") is an influential early time-sharing operating system based on the concept of a single-level memory.Dennis M. Ritchie, "The Evolution of the Unix Time-sharing System", Communications of t ...

VM/CMS VM (often: VM/CMS) is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers. Design The heart o ...

OpenVMS OpenVMS, often referred to as just VMS, is a multi-user, multiprocessing and virtual memory-based operating system. It is designed to support time-sharing, batch processing, transaction processing and workstation applications. Customers using Op ...

MP/M MP/M (Multi-Programming Monitor Control Program) is a discontinued multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each u ...

Concurrent CP/M MP/M (Multi-Programming Monitor Control Program) is a discontinued multi-user version of the CP/M operating system, created by Digital Research Digital Research, Inc. (DR or DRI) was a privately held American software company created by ...

Concurrent DOS Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by ...

FlexOS FlexOS is a discontinued modular real-time multiuser multitasking operating system ( RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. Developed by Digital Research's Flexible Automation Business ...

Multiuser DOS Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by ...

REAL/32 Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by ...

OASIS In ecology, an oasis (; : oases ) is a fertile area of a desert or semi-desert environment THEOS THEOS, which translates from Greek as "God", is an operating system which started out as OASIS, a microcomputer operating system for small computers that use the Zilog Z80, Z80 processor. When the operating system was launched for the IBM Per ...

PC-MOS PC-MOS/386 is a multi-user, multitasking computer operating system produced by The Software Link (TSL), announced at COMDEX in November 1986 for February 1987 release. PC-MOS/386, a successor to PC-MOS, can run many MS-DOS programs on the host ...

TSX-32 TSX-32 is a discontinued general purpose 32-bit multi-user multitasking operating system for the x86 architecture platform, with a command line user interface. It is compatible with some 16-bit DOS applications and supports the FAT16 and FA ...

and

VM/386 VM/386 is a multitasking Multi-user environment or 'control program' that took early advantage of the capabilities of Intel's 386 processor. By utilizing Virtual 8086 mode, users were able to run their existing text-based and graphical DOS soft ...

. Some multi-user operating systems such as

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

versions from the

Windows NT Windows NT is a Proprietary software, proprietary Graphical user interface, graphical operating system produced by Microsoft as part of its Windows product line, the first version of which, Windows NT 3.1, was released on July 27, 1993. Original ...

family support simultaneous access by multiple users (for example, via

Remote Desktop Connection Remote Desktop Protocol clients allow users to connect to servers running Remote Desktop Services, Azure Virtual Desktop, or non-Microsoft server software to enable Remote desktop software, remote desktop functionality. Since the release of Remote ...

) as well as the ability for a user to disconnect from a local session while leaving processes running (doing work on their behalf) while another user logs into and uses the system. The operating system provides isolation of each user's processes from other users, while enabling them to execute concurrently{{dubious, date=July 2014.

Management systems A management system is a set of policies, processes and procedures used by an organization to ensure that it can fulfill the tasks required to achieve its objectives. These objectives cover many aspects of the organization's operations (includi ...

are implicitly designed to be used by multiple users, typically one

system administrator An IT administrator, system administrator, sysadmin, or admin is a person who is responsible for the upkeep, configuration, and reliable operation of computer systems, especially multi-user computers, such as Server (computing), servers. The ...

or more and an

end-user In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ultimately use a product. The end user stands in contrast to users who support or maintain the product, such as sysops, system administrato ...

community. The complementary term, single-user, is most commonly used when talking about an operating system being usable only by one person at a time, or in reference to a single-user

software license agreement An end-user license agreement or EULA () is a legal contract between a software supplier and a customer or End user, end-user. The practice of selling licenses to rather than copies of software predates the recognition of software copyright, w ...

. Multi-user operating systems such as Unix sometimes have a single user mode or runlevel available for emergency maintenance. Examples of single-user operating systems include

MS-DOS MS-DOS ( ; 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 op ...

OS/2 OS/2 is a Proprietary software, proprietary computer operating system for x86 and PowerPC based personal computers. It was created and initially developed jointly by IBM and Microsoft, under the leadership of IBM software designer Ed Iacobucci, ...

and

Classic Mac OS Mac OS (originally System Software; retronym: Classic Mac OS) is the series of operating systems developed for the Mac (computer), Macintosh family of personal computers by Apple Computer, Inc. from 1984 to 2001, starting with System 1 and end ...

References

External links

Interix in a Multi-User Windows TSE Environment
paper about the

multi-user model and MS-Windows NT TSE Operating system technology

See also

References

External links