This is a list of operating systems. Computer operating systems can be categorized by technology, ownership, licensing, working state, usage, and by many other characteristics. In practice, many of these groupings may overlap. Criteria for inclusion is notability, as shown either through an existing Wikipedia article or citation to a reliable source.

Proprietary

Acorn Computers

Amazon

Amiga Inc.

Amstrad

Apple

Apollo Computer, Hewlett-Packard

Atari

BAE Systems

Be Inc.

Bell Labs

Non-Unix Operating Systems:

Burroughs Corporation, Unisys

Commodore International

Control Data Corporation

Lower 3000 series

Upper 3000 series

6x00 and related Cyber

CloudMosa

Convergent Technologies

Cromemco

Data General

Datapoint

DDC-I, Inc.

Digital Research, Inc.

Digital Equipment Corporation, Compaq, Hewlett-Packard, Hewlett Packard Enterprise

ENEA AB

Fujitsu

GEC Computers

General Electric, Honeywell, Bull

Google

Green Hills Software

Harris Computer Systems

Heathkit, Zenith Data Systems

Hewlett-Packard, Hewlett Packard Enterprise

Honeywell

Huawei

Intel Corporation

IBM

On early mainframes: 1410, 7010, 704, 709, 7090, 7094, 7040, 7044, 7030

On S/360, S/370, and successor mainframes

On PC and Intel x86 based architectures

On other hardware platforms

International Computers Limited

Jide

Jolla

KaiOS

Lynx Real-time Systems, LynuxWorks, Lynx Software Technologies

Meizu

Microsoft Corporation

MITS

MontaVista

Motorola

NCR Corporation

NeXT

Nintendo

Novell

Open Mobile Platform

Quadros Systems

RCA

RoweBots

Samsung Electronics

Scientific Data Systems (SDS)

SCO, SCO Group

Silicon Laboratories (formerly Micrium Inc.)

Sinclair Research

Sony

SYSGO

Tandem Computers, Compaq, Hewlett-Packard, Hewlett Packard Enterprise

Tandy Corporation

TCSC (later NCSC)

Texas Instruments

TRON Project

UNIVAC, Unisys

Wang Laboratories

Weston Embedded Solutions

Wind River Systems

Zilog

Other

Lisp-based

For Elektronika BK

Non-standard language-based

Other proprietary non-Unix-like

Other proprietary Unix-like and POSIX-compliant

Non-proprietary

Unix or Unix-like

Non-Unix

Research

Unix or Unix-like

Non-Unix

Disk operating systems (DOS)

Network operating systems

Generic, commodity, and other

Hobby

Embedded

Mobile operating systems

Routers

Other embedded

LEGO Mindstorms

Capability-based

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