Modular building block OS adaptible to various configurations. 8080, 8086 and 68000 families.

Multi-Solutions, USA

Operating system for the ALTOS computer (?).

USA

Complementary version of FreeRTOS, with common functionality but designed specifically for safety-critical implementation.

Wittenstein High Integrity Systems, Real Time Engineers Ltd., UK

Semi-Automatic Ground Environment system. Control Program for IBM AN/FSQ7 to monitor weapons systems. First real-time control system.

IBM, USA

Semi-Automatic Business Related Environment. The first major transaction processing system, developed by IBM and American Airlines for the IBM 7090.

IBM, USA

Distributed OS supporting varying degrees of transparency.

Univeristy of Arizona, USA

General purpose Linux distribution used commonly as a mobile operating system combining the Linux kernel for a particular hardware platform.

Jolla, Finland

See rojan.

Minimalistic 32-bit x86 operating system kernel for network server appliances running on standard PC hardware.

Now NX-OS.

Cisco Systems, USA

Portable microkernel and a set of operating system services.

Real time OS for Mod Comp Computers.

USA

Operating system and operating environment written in Scheme atop a virtual machine which provides an abstraction layer between the hardware and the operating system, implying ease of porting between widely varying processors and other hardware.

Implementation of (a subset of) Scheme that runs inside the Linux Kernel OS, so you can dynamically debug your device-drivers.

OpenSolaris based complete open-source operating system.

Germany

Line of software including an improved AGAT-DOS.

Computing Center - USSR Academy of Science, Russia

Pre-emptive, priority-based direct message passing real-time kernel.

Sciopta Systems, Switzerland

Tiny Real-Time Preemptive Operating System intended for use with Single-Chip Microcontrollers.

Russia

The first 32-bit graphical user interface for UNIX Systems running on Intel processor-based computers. Based on SCO Unix.

Samsung Electronics, Korea

Aka Xinuos OpenServer, previously SCO UNIX and SCO Open Desktop (SCO ODT), is a closed source computer operating system developed by Santa Cruz Operation (SCO), later acquired by SCO Group, and now owned by Xinuos.

SCO Group, USA

AT&T UNIX System V Release 3 based.

SVR5 (UnixWare 7) based kernel with SCO OpenServer 5 application and binary compatibility, system administration, and user environments.

First volume commercial product licensed by AT&T to use the UNIX System trademark (1989). Derived from AT&T System V Release 3.2 with an infusion of Xenix device drivers and utilities plus most of the SVR4 features.

SCO Group, USA

Commercial successor to SCO Xenix.

Supervisory Control Of Program Execution or Simultaneous Control Of Program Execution. File-oriented system using mass storage, random access devices. Productized version of Chippewa.

Control Data, USA

Ads the Record manager features. Base for NOS/BE.

Operating system specifically aimed at network appliances (webcams, ip routers).

University of Arizona, USA

Supervisory Control Program.

GEC Computers, USA

System Control Program. Basic OS for the Burroughs B700 series.

USA

Secure Operating System (DOD A1/B3) Multilevel security.

DEC, USA

DOS acquired by Bill Gates to create MS_DOS. See 86-DOS.

Seattle Computer Products, USA

Real-time embedded operating system for the NetScreen range of hardware firewall devices from Juniper Networks.

Lastest version.

Operating System for 6809.

Software Dynamics, USA

Small Devices Portable Operating System. Mini operating system providing basic scheduling services (cooperative and real time modes) and an hardware abstraction layer enabling the user to quickly developp embedded applications minimizing the need to learn specific processor architectural details.

Mostly a clone of the RISC/os.

Sumitomo Electric, Japan

Batch Serial Operating System for the SEL 810A/810B minicomputer.

USA

Unix on Series/1. CMI version of AT&T's UNIX System V OS.

Object Oriented system based on a message passing kernel.

Soft Hard Real-time Kernel. Completely configurable kernel architecture designed for supporting hard, soft, and non real-time applications with interchangeable scheduling algorithms. Evolution of the Hartik Kernel and it is based on the OSLib Project.

Sant'Anna School of Advanced Studies, Pisa, Italy

Computer operating system based on the .NET Framework and related programming language C#.

Small OS, written in 3 months entirely in assembly, that is functional enough to run programs.

Industrial control system based on FlexOS.

Digital Research, USA

Operating system for the SDS Sigma 7 real-time data processing computer.

USA

Scout in Linux Kernel. Linux kernel module which transforms a standard Linux OS into Scout.

University of Princeton, USA

Lisp environment atop Unix .

Open source micro real time kernel.

SpanIdea, USA

Embedded Programming Platform.

Erik Moqvist, Sweden

RTOS designed special for AVR microcontrollers.

Formerly known as xPC Target. Environment for simulating and testing Simulink and Stateflow models in real-time on the physical system.

MathWorks, USA

Multitasking operating system found on the Sinclair QL personal computer and its clones.

Sinclair, UK

Research operating system written mostly in managed code (C#).

Microsoft, USA

Port by SNI of Unix to the MIPS architecture.

Siemens Nixdorf, Germany

Range of operating systems for Norsk Data's line of minicomputers.

Norwegian Institute of Technology, Norsk Data, Norway

Multi-user system that constituted the software platform for the NORD-1 range of terminal servers.

Real-time multitasking system was used for Norsk Data's server machines (such as the Nord-10, -100).

Simultaneous Processing Operating System.

Control Data, USA

Time-sharing operating system for airline reservations.

Russia

Operating system for CII 1070 and IRIS computers.

Compagnie internationale pour l'informatique, France

Commercial desktop OS for PCs.

Linux distribution.

Safe Language Kernel Project. OS infrastructure for extensible systems.

Cornell University, USA

SmartEdge Operating System.

Ericsson, Sweden

Illumos distribution for cloud computing with Kernel-based Virtual Machine integration.

Joyent, USA

Derivative from QDOS running on Atari computers in monochrome mode (640x400). It does not get any BASIC interpreter. "SMS" should stand for Small Multitasking System or Small Machine System.

Full re-write of QDOS. Developped from SMS2 for the Miracle systems' QXL card.

Tony Tebby, France

Born from the fusion of SMSQ and of the level "E" (thus the name) device drivers first developped for the Atari QL emulator sold by Jochen Merz Software.

Tony Tebby, France

M. M. Somia, USA

Sistema Operacional em Disco.

Instituto Tercio Pacitti - NCE, Brazil

Simplified OS for Distributed applications.

USA

Operating system for a Distributed System developed on the IBM Series/1.

Univeristy of Delaware, USA

One of the first Linux distributions.

Peter MacDonald, Canada

Simple, easy, fast realtime 32bit GUI OS.

Bogdan Ontanu, Romania

System V-based replacement for SunOS.

Sun Microsystems, USA

Successor to SunOS 4.x; based on SVR4 instead of BSD.

First 64-bit Solaris release – names from this point drop "2.", otherwise would've been Solaris 2.7.

Single-User Research Operating System. Written in Concurrent Pascal, to demonstrate its concurrency mechanism at the California Institute of Technology.

Per Brinch Hansen, USA

Single Address Space Operating Systems. OS providing an unique address to objects in a global address space (SAS), much like Mungi.

Arizona State University, USA

Server Oriented Operating System. Operating system (OS) specially designed for embedded systems.

David Donari, Leo Ordinez, Rodrigo Santos, Brazil

Minimal DOS for Z80 machines.

Japan

SHARE Operating System. Improvement on the General Motors GM-NAA I/O operating system, the first operating system.

SHARE user group, USA

Standalone OS for Data General Nova & Supernova.

USA

Sophisticated OS for the Apple III.

USA

SOMIW Operating System. Object-oriented operating system implemented on top of UNIX.

INRIA, France

Approach to operating systems which uses multiple protection domains rather than a single kernel to provide operating system services.

University of Santa Barbara, USA

Aka SpartaDOS 4.0. Disk operating system for the Atari 8-bit family of computers that closely resembles MS-DOS.

ICD, Fine Tooned Engineering, USA

Real-time, ROM-based development system.

Infosphere, USA

Extensible OS written in Modula-3.

University of Washington, USA

Small general-purpose computer operating system together with extra functions, such as kana-enabled COBOL, suited for office-computer applications that aimed to be user friendly.

Fujitus, Japan

Operating system based on a microkernel.

South Africa

Distributed multiplatform OS. Not related to the Spring Kernel, a real-time system.

Sun Microsystems, USA

Distributed operating system that provides a single system image to a cluster of workstations.

U.C. Berkeley, USA

Service Router Operating System. Based on VxWorks.

Alcatel-Lucent, USA

Smoke Signal Broadcasting. A variant of FLEX in most respects.

TSC ?, USA

Operating system of 6809 Computer board.

USA

System Support Program. operating system for the IBM System/34 and System/36 minicomputers. SSP was a command-based operating system.

IBM, USA

Graphical user interface for the Xerox Star.

Xerox, USA

One of two major operating systems developed for the Cm* multiprocessor. Based on concept of task forces.

Carnegie-Mellon University, USA

Realtime OS for the Z80A.

National Semiconductors, USA

Free, extremely simple, amazingly tiny and very fast real-time operating system (RTOS) designed for deeply embedded applications.

Live CD protected-mode OS.

Stefan Mayer, Austria

Real time operating system. It runs on 680x0 processors and may be adapted to ColdFire processors. Although designed for embeded systems, it could be easily extended to run on any computer system.

Tony Tebby, France

Experimental operating system designed to serve as an efficient customizable substrate for modern programming languages.

Secure Trusted Operating Program. Monolithic kernel operating system. Though it provides a Linux-compatible API, STOP is not derived from Unix or any Unix-like system. TCSEC A1-class, secure OS for SCOMP hardware.

BAE Systems, USA

Desktop focused distribution based on Nexenta Core Platform 2.0.

Microcontroller operating system designed to bring the software innovation model that has made computers and smartphones enormously successful to microcontroller hardware.

Statify Labs, USA

Operating system for Stratus-32 Computers.

Stratus Technologies, USA

Developed by Stratus, and used for IBM System/88, Original equipment manufacturer from Stratus.

IBM, USA

Silicon TRON. Hardware implementation of a real-time kernel.

Japan

Experimental OS for the IBM S/360.

USA

General Purpose OS kernel for the HP 9000 Series 500.

USA

Later SunOS. Bundled with 68000-based Sun-1 system. No windowing system.

Sun Microsystems, USA

Version of UNIX for Z8002.

SGS-Ates, Italy

BSD-based Unix system used on early Sun hardware.

Sun Microsystems, USA

Support for 68010-based Sun-1 and Sun-2 systems. Introduced Sun Windowing System.

Coincided with release of 68020-based Sun-3 hardware.

Optional System V tape offered utilities and development libraries.

First support for Sun-4 series.

New virtual memory system, dynamic linking, automounter, System V STREAMS I/O. Sun386i support.

See Solaris.

CP/M 2.2 with SuperDOS as BDOS replacement.

USA

Port of System V Release 4.2MP with features adopted from BSD and Linux for NEC SX architecture supercomputers.

USA

Linux distribution.

SUSE, Germany

Designed for servers, mainframes, and workstations but can be installed on desktop computers for testing as well.

SUSE, Germany

Sistema Virtual'nykh Mashin. IBM VM/370 clone.

Russia

Added Russian language capability.

Added RIAD-3 support.

Single Virtual Storage. Refers to Release 1 of Operating System/Virtual Storage 2 (OS/VS2); it is the successor system to the MVT option of Operating System/360.

IBM, USA

Pretty standard, kernel based OS, but that actually boots and works to some extent.

Complete SDN operating system based on Open Network Linux (ONL), an open source effort within the Open Compute Project.

Big Switch Networks, USA

Modern, independently originated OS. See AtheOS.

K. Van Der Vliet, K. de Vos, R. Caudill, A. Klenke, H. Isaksson, UK

Discontinued mobile operating system and computing platform designed for smartphones.

Symbian, UK

Successor to Symbian OS.

Symbian, UK

SYmbiosis Multitasking Based Operating System. GUI based modern micro-kernel OS for x86, ARM and PowerPC processors. Used and developed further at Technical University of Munich.

Miray Software, UK

SYstem for MOBIle applications. proprietary modern and mobile real-time operating system. Designed for the area of embedded and mobile systems.

Miray Software, Germany

The first of the modern OS that dynamically generated code at runtime. Although it was written in MC68000 assembly, it opened the path to projects like Aegis and Synthetix.

Henry Massalin, USA

OGI's Synthetix project of fine-grained incremental partial evaluation in OS kernels, using a combination of highly isolated system components, and dynamic code generation. Sponsored by ARPA, Intel, and Hewlett-Packard.

OGI School of Science and Engineering, USA

Operating system for the Philco-2000 computer.

Philco, USA

System Executive. A time-sharing monitor for SIGMA/2 and small IBM S/360 computers.

USA

Microkernel based multiprocessor, multitasking, multithreading operating system for the IBM-PC Intel i386 systems. It is developed in Department of Computer Science of Bahahuddin Zakariya University, Multan Pakistan.

Bahahuddin Zakariya University, Multan, Pakistan

IBM version of Stratus/32 OS.

IBM, Stratus Computer, USA