Editing Multiuser DOS (section)

{{Short description|Family of CP/M- and DOS-compatible multi-user multi-tasking operating systems}}
{{Use dmy dates|date=April 2019|cs1-dates=y}}
{{Use list-defined references|date=December 2021}}
{{Infobox OS 
| name                   = Multiuser DOS
| logo                   = 
| screenshot             = Novell DR Multiuser DOS Release 5.1 720x400.png
| caption                = Novell DR Multiuser DOS Release 5.1
| developer              = [[Digital Research]], [[Novell]]
| source_model           = [[Closed source]]
| kernel_type            = [[Monolithic kernel]]
| supported_platforms    = [[x86]], [[Motorola 68000|68000]]
| ui                     = [[Command-line interface]] ([[COMMAND.COM]])
| family                 = [[CP/M]]
| released               = 
| latest_release_version = 7.22 R18
| latest_release_date    = {{Start date and age|2005|04|21|df=yes}} (REAL/32: 7.95<!-- somewhen between 2006 and 2010 -->)
| latest_test_version    = 
| latest_test_date       = 
| marketing_target       = 
| programmed_in          = 
| prog_language          = 
| language               = [[English language|English]]
| updatemodel            = Re-installation
| package_manager        = None
| working_state          = Discontinued
| license                = [[Proprietary software|Proprietary]]
| discontinued           = yes
| website                = Various (see notes)
}}

'''Multiuser DOS''' is a [[Real-time operating system|real-time]] multi-user multi-tasking [[operating system]] for [[IBM Personal Computer|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 [[Digital Research]] and acquired and further developed by [[Novell]] in 1991.<ref name="Scott_1991"/><ref name="BW_1991"/><ref name="Allchin_1992"/> Its ancestry lies in the earlier Digital Research [[8-bit]] operating systems [[CP/M]] and [[MP/M]], and the [[16-bit]] single-tasking [[CP/M-86]] which evolved from CP/M.

When Novell abandoned Multiuser DOS in 1992, the three master [[value-added reseller]]s (VARs) DataPac Australasia, [[Concurrent Controls]]<ref name="Barney_1994_CCI"/> and [[Intelligent Micro Software]]<ref name="Pontin_1995_IMS"/> were allowed to take over and continued independent development into Datapac Multiuser DOS and System Manager, CCI Multiuser DOS, and IMS Multiuser DOS and REAL/32.<ref name="Pontin_1995_IMS"/>

The [[FlexOS]] line, which evolved from [[Concurrent DOS 286]] and [[Concurrent DOS 68K]], was sold off to [[Integrated Systems Inc.|Integrated Systems]], Inc. (ISI) in July 1994.