Darwin (operating system)

Computer operating system

"Darwin (kernel)" redirects here. For the article about the kernel, see XNU.

Operating system

DarwinDeveloper| Apple Inc.

|

Written in| C, C++, Objective-C, assembly language
OS family| Unix-like,[1][2] FreeBSD,[3] BSD[4]
Working state| Current
Source model| currently open source with proprietary components[citation needed], previously open source
Initial release| November 15, 2000; 23 years ago (2000-11-15)
Latest release| 23.4.0 / March 5, 2024; 3 months ago (2024-03-05)
Repository| github.com/apple-oss-distributions/distribution-macOS
Platforms| Current: x86-64, 64-bit ARM, 32-bit ARM (32-bit ARM support is closed-source)
Historical: PowerPC (32-bit and 64-bit), IA-32
Kernel type| Hybrid (XNU)
Influenced by| NeXTSTEP, FreeBSD, BSD
Default
user interface| Command-line interface (Unix shell)
License| Mostly Apple Public Source License (APSL), with closed-source drivers[5]
Official website| opensource.apple.com
Part of a series on

macOS

Features

* History
* Transition to Intel processors
* Transition to Apple silicon
* Architecture
* Built-in apps
* List of applications
* List of games

Versions

* Rhapsody (Developer Release)
* Hera (Server 1.0)
* Kodiak (Public Beta)
* Cheetah (10.0)
* Puma (10.1)
* Jaguar (10.2)
* Panther (10.3)
* Tiger (10.4)
* Leopard (10.5)
* Snow Leopard (10.6)
* Lion (10.7)
* Mountain Lion (10.8)
* Mavericks (10.9)
* Yosemite (10.10)
* El Capitan (10.11)
* Sierra (10.12)
* High Sierra (10.13)
* Mojave (10.14)
* Catalina (10.15)
* Big Sur (11)
* Monterey (12)
* Ventura (13)
* Sonoma (14)
* Sequoia (15)

Applications

* App Store
* Automator
* Books
* Calculator
* Calendar
* Chess
* Contacts
* Dashboard
* Dictionary
* DVD Player
* FaceTime
* Finder
* Game Center
* Grapher
* iTunes (history)
* Launchpad
* Mail
* Messages
* Music
* Notes
* Notification Center
* Photo Booth
* Podcasts
* Photos
* Preview
* QuickTime
* Reminders
* Safari (version history)
* Sherlock
* Stickies
* TextEdit
* Time Machine

Utilities

* Activity Monitor
* AirPort Utility
* Archive Utility
* Audio MIDI Setup
* Bluetooth File Exchange
* ColorSync
* Console
* Crash Reporter
* DigitalColor Meter
* Directory Utility
* DiskImageMounter
* Disk Utility
* Font Book
* Grab
* Help Viewer
* Image Capture
* Installer
* Keychain Access
* Migration Assistant
* Network Utility
* ODBC Administrator
* Remote Install Mac OS X
* System Preferences
* System Information
* Terminal
* Universal Access
* VoiceOver

Related

* Classic Mac OS
* Copland
* NeXTSTEP
* Rhapsody
* Darwin

* v
* t
* e

Darwin is the core Unix-like operating system of macOS (previously OS X and Mac OS X), iOS, watchOS, tvOS, iPadOS, visionOS, and bridgeOS. It previously existed as an independent open-source operating system, first released by Apple Inc. in 2000. It is composed of code derived from NeXTSTEP, FreeBSD,[3] other BSD operating systems,[6] Mach, and other free software projects' code, as well as code developed by Apple.

Darwin is mostly POSIX-compatible, but has never, by itself, been certified as compatible with any version of POSIX. Starting with Leopard, macOS has been certified as compatible with the Single UNIX Specification version 3 (SUSv3).[7][8][9]

## History[edit]

Simplified history of Unix-like operating systems

The heritage of Darwin began with Unix derivatives supplemented by aspects of NeXT's NeXTSTEP operating system (later, since version 4.0, known as OPENSTEP), first released in 1989. After Apple bought NeXT in 1996, it announced it would base its next operating system on OPENSTEP. This was developed into Rhapsody in 1997, Mac OS X Server 1.0 in 1999, Mac OS X Public Beta in 2000, and Mac OS X 10.0 in 2001.

In 1999, Apple announced it would release the source code for the Mach 2.5 microkernel, BSD Unix 4.4 OS, and the Apache Web server components of Mac OS X Server.[10] At the time, interim CEO Steve Jobs alluded to British naturalist Charles Darwin by announcing "because it's about evolution".[11] In 2000, the core operating system components of Mac OS X were released as open-source software under the Apple Public Source License (APSL) as Darwin; the higher-level components, such as the Cocoa and Carbon frameworks, remained closed-source.

Up to Darwin 8.0.1, released in April 2005, Apple released a binary installer (as an ISO image) after each major Mac OS X release that allowed one to install Darwin on PowerPC and Intel x86 systems as a standalone operating system.[12] Minor updates were released as packages that were installed separately. Darwin is now only available as source code. As of January 2023, Apple no longer mentions Darwin by name on its Open Source website and only publishes an incomplete collection of open-source projects relating to macOS and iOS.

## Design[edit]

Diagram of macOS architecture

### Kernel[edit]

Main articles: XNU and Mach (kernel)

The kernel of Darwin is XNU, a hybrid kernel which uses OSFMK 7.3[13] (Open Software Foundation Mach Kernel) from the OSF, various elements of FreeBSD (including the process model, network stack, and virtual file system),[14] and an object-oriented device driver API called I/O Kit.[15] The hybrid kernel design provides the flexibility of a microkernel[16][failed verification – see discussion] and the performance of a monolithic kernel.[17]

### Hardware and software support[edit]

The last bootable full release of Darwin supported 32-bit and 64-bit Apple PowerPC systems and 32-bit Intel PCs.[18]

Darwin currently includes support for the 64-bit x86-64 variant of the Intel x86 processors used in Intel-based Macs and the 64-bit ARM processors used in the iPhone 5S and later, the 6th generation iPod Touch, the 5th generation iPad and later, the iPad Air family, the iPad Mini 2 and later, the iPad Pro family, the fourth generation and later Apple TVs, the HomePod family, and Macs with Apple silicon such as the 2020 Apple M1 Macs, as well as the Raspberry Pi 3B.[19][20] An open-source port of the XNU kernel exists that supports Darwin on Intel and AMD x86 platforms not officially supported by Apple, though it does not appear to have been updated since 2009.[21] An open-source port of the XNU kernel also exists for ARM platforms, though it has not been updated since 2016.[22] Older versions supported some or all of 32-bit PowerPC, 64-bit PowerPC, 32-bit x86, and 32-bit ARM.

It supports the POSIX API by way of its BSD lineage (largely FreeBSD userland), so a large number of programs written for various other UNIX-like systems can be compiled on Darwin with no changes to the source code.

Darwin does not include many of the defining elements of macOS, such as the Carbon and Cocoa APIs or the Quartz Compositor and Aqua user interface, and thus cannot run Mac applications. It does, however, support a number of lesser-known features of macOS, such as mDNSResponder, which is the multicast DNS responder and a core component of the Bonjour networking technology, and launchd, an advanced service management framework.

## License[edit]

In July 2003, Apple released Darwin under version 2.0 of the Apple Public Source License (APSL), which the Free Software Foundation (FSF) classifies as a free software license incompatible with the GNU General Public License.[23] Previous versions were released under an earlier version of the APSL license, which did not meet the FSF definition of free software, although it did meet the requirements of the Open Source Definition.[24]

## Derived projects[edit]

Due to the free software nature of Darwin, there have been projects that aim to modify or enhance the operating system.

### OpenDarwin[edit]

GNOME running on GNU-Darwin

OpenDarwin was a community-led operating system based on the Darwin system. It was founded in April 2002 by Apple Inc. and Internet Systems Consortium. Its goal was to increase collaboration between Apple developers and the free software community. Apple benefited from the project because improvements to OpenDarwin would be incorporated into Darwin releases; and the free/open source community benefited from being given complete control over its own operating system, which could then be used in free software distributions such as GNU-Darwin.[25]

On July 25, 2006, the OpenDarwin team announced that the project was shutting down, as they felt OpenDarwin had "become a mere hosting facility for Mac OS X related projects", and that the efforts to create a standalone Darwin operating system had failed.[26] They also state: "Availability of sources, interaction with Apple representatives, difficulty building and tracking sources, and a lack of interest from the community have all contributed to this."[27] The last stable release was version 7.2.1, released on July 16, 2004.[28]

### PureDarwin[edit]

PureDarwin is a project to create a bootable operating system image from Apple's released source code for Darwin.[29] Since the halt of OpenDarwin and the release of bootable images since Darwin 8.x, it has been increasingly difficult to create a full operating system as many components became closed source. In 2015 the project created a preview release based on Darwin 9 with an X11 GUI,[30] followed by a command-line only 17.4 Beta based on Darwin 17.[31]

### Other derived projects[edit]

Window Maker in XDarwin

* XQuartz is a component of the X Window System that runs on macOS (Darwin). XDarwin, before the introduction of Apple's X11.app.
* GNUstep is a free software implementation of the Cocoa (formerly OpenStep) Objective-C frameworks, widget toolkit, and application development tools for Unix-like operating systems.
* Window Maker, a window manager designed to emulate the NeXT GUI as part of the wider GNUstep project.
* MacPorts (formerly DarwinPorts), Fink, and Homebrew are projects to port UNIX programs to the Darwin operating system and provide package management. In addition, several standard UNIX package managers—such as RPM, pkgsrc, and Portage—have Darwin ports. Some of these operate in their own namespace so as not to interfere with the base system.
* GNU-Darwin was a project that ports packages of free software to Darwin. They package OS images in a way similar to a Linux distribution.
* The Darwine project was a port of Wine that allows one to run Microsoft Windows software on Darwin.
* SEDarwin was a port of TrustedBSD mandatory access control framework and portions of the SELinux framework to Darwin.[32] It was incorporated into Mac OS X 10.5.[33]
* The Darbat project was an experimental port of Darwin to the L4 microkernel family. It aims to be binary compatible with existing Darwin binaries.[34]
* The Darling project is a compatibility layer for running macOS binaries on Linux systems. It uses some Darwin source code.[35]
* There are various projects that focus on driver support: e.g., wireless drivers,[36][37] wired NIC drivers[38][39][40] modem drivers,[41] card readers,[42] and the ext2 and ext3 file systems.[43][44]
* DarwinBSD Project is a Darwin project using pkgsrc for packages. It is an open source project.[45]

## See also[edit]

* Free and open-source software portal

* A/UX
* mkLinux
* OSF/1

## References[edit]

1. ^ "Kernel Architecture Overview". Kernel Programming Guide.
2. ^ "darwin-xnu/README.md at master". GitHub. Archived from the original on March 31, 2019. Retrieved November 21, 2019.
3. ^ a b "Apple BSD Overview". Apple. 2002. Retrieved January 1, 2002.
4. ^ "Apple - Public Source - Darwin FAQ". Archived from the original on November 19, 2004. Retrieved August 9, 2021.
5. ^ "Binary Drivers required for PureDarwin". Archived from the original on November 18, 2009. Retrieved July 20, 2009.
6. ^ "1. System Overview". NeXTstep Concepts. NeXT. Archived from the original on November 21, 2021. Retrieved March 26, 2021.
7. ^ "Mac OS X Leopard - Technology - UNIX". Leopard Technology Overview. Apple Inc. Archived from the original on December 27, 2008. "Leopard is now an Open Brand UNIX 03 Registered Product, conforming to the SUSv3 and POSIX 1003.1 specifications for the C API, Shell Utilities, and Threads."
8. ^ The Open Group (May 18, 2007). "Mac OS X Version 10.5 Leopard on Intel-based Macintosh computers certification". Retrieved February 11, 2013.
9. ^ "macOS version 10.13 High Sierra on Intel-based Mac computers". The Open Group. Retrieved November 19, 2017.
10. ^ Walsh, Jeff (March 22, 1999). "Apple goes open source with key OS components". InfoWorld. Vol. 21, no. 12\. IDG InfoWorld. p. 40. Retrieved February 17, 2020.
11. ^ Kahney, Leander. "Apple Opens OS Code". Wired. Condé Nast. Retrieved February 17, 2020.
12. ^ "Apple ISO download directory". Archived from the original on October 7, 2016.
13. ^ Jim Magee. WWDC 2000 Session 106 - Mac OS X: Kernel. 14 minutes in. Archived from the original on December 11, 2021.
14. ^ "Mac Technology Overview: Kernel and Device Drivers Layer". Apple Developer Connection. Retrieved February 11, 2013.
15. ^ Singh, Amit (January 7, 2004). "XNU: The Kernel". Archived from the original on June 2, 2020. Retrieved February 11, 2013.
16. ^ Roch, Benjamin. "Monolithic kernel vs. Microkernel". CiteSeerX 10.1.1.89.9877.
17. ^ "Additional Features". Porting UNIX/Linux Applications to OS X. Apple Inc.
18. ^ "Darwin 8.0.1 Release Notes". April 29, 2005.
19. ^ "XNU board config for BCM2837". GitHub. December 16, 2021.
20. ^ "Raspberry Pi 3 Model B". "Quad Core 1.2GHz Broadcom BCM2837"
21. ^ "Voodoo XNU Kernel Source". Requires an Apache SVN client.
22. ^ "XNU on ARMv7". GitHub. January 25, 2022.
23. ^ "FSF's Opinion of the Apple Public Source License (APSL) 2.0".
24. ^ "The Problems with older versions of the Apple Public Source License (APSL)".
25. ^ "OpenDarwin". OpenDarwin Project. Archived from the original on January 6, 2006.
26. ^ Schofield, Jack (July 26, 2006). "OpenDarwin Shutting Down". The Guardian. Retrieved March 18, 2023.
27. ^ OpenDarwin Core Team and Administrators (July 25, 2006). "OpenDarwin Shutting Down". OpenDarwin Project. Archived from the original on August 4, 2006.
28. ^ "OpenDarwin 7.2.1 Released". August 5, 2004. Archived from the original on August 5, 2004. Retrieved October 7, 2019.
29. ^ "PureDarwin".
30. ^ PureDarwin Xmas (2015)
31. ^ "PureDarwin 17.4 Beta". GitHub. PureDarwin. November 30, 2019. Retrieved January 11, 2020.
32. ^ "Security Enhanced Darwin". SEDarwin. January 22, 2007. Archived from the original on October 5, 2011.
33. ^ "What's New In Mac OS X: Mac OS X v10.5". Mac OS X Reference Library. Apple Inc. November 13, 2009. Archived from the original on December 8, 2009.
34. ^ "L4/Darwin (aka Darbat)". Ertos.nicta.com.au. May 9, 2007. Archived from the original on December 19, 2013.
35. ^ "Darling: macOS translation layer for Linux". www.darlinghq.org. Retrieved January 11, 2020.
36. ^ yuriwho (May 5, 2002). "WirelessDriver Home Page". Wirelessdriver.sourceforge.net. Retrieved July 12, 2010.
37. ^ "iwi2200 Darwin". SourceForge. March 27, 2009. Retrieved June 13, 2010.
38. ^ "Port BSD tulip driver(s) to Darwin OS | Download Port BSD tulip driver(s) to Darwin OS software for free at". SourceForge.net. Retrieved July 12, 2010.
39. ^ "RealTek network driver for Mac OS X/Darwin". SourceForge. March 15, 2006. Retrieved June 3, 2010. Project inactive since March 15, 2006.
40. ^ fansui; et al. (August 1, 2007). "RTL8150LMEthernet". SourceForge. Retrieved June 13, 2010.
41. ^ "ZyXEL Modem Drivers for OS X/Darwin | Download ZyXEL Modem Drivers for OS X/Darwin software for free at". SourceForge.net. May 14, 2002. Retrieved July 12, 2010.
42. ^ "Mac OS X PC Card ATA Driver". Pccardata.sourceforge.net. December 20, 2001. Retrieved July 12, 2010.
43. ^ "Mac OS X Ext2 Filesystem | Download Mac OS X Ext2 Filesystem software for free at". SourceForge.net. October 14, 2002. Retrieved July 12, 2010.
44. ^ "ext2 filesystem in user space". SourceForge. July 14, 2008. Retrieved June 13, 2010.
45. ^ "DarwinBSD". darwinbsd.tk. Retrieved April 7, 2023.

## External links[edit]

* Darwin Releases at Apple Developer Connection
* source code of individual packages
* Hexley, the Darwin mascot
* PureDarwin.org
* The Apple Museum "MacOS X Build Numbers" at the Wayback Machine (archived December 25, 2011)

* v
* t
* e

Darwin-derived operating systems

History|

| Pre-Darwin|

* Unix
* BSD
* Mach
* NeXTSTEP
* OpenStep
* GNUstep
* Rhapsody

|

Macintosh|

| Mac OS X,
OS X,
macOS
(history)|

| Mac OS X
Server|

* Mac OS X Server 1.0 (Hera, Rhapsody)
* 10.0 (Cheetah)
* 10.1 (Puma)
* 10.2 (Jaguar)
* 10.3 (Panther)
* 10.4 (Tiger)
* 10.5 Leopard Server
* 10.6 Snow Leopard Server

|

* Mac OS X Public Beta (Kodiak)
* 10.0 (Cheetah)
* 10.1 (Puma)
* 10.2 (Jaguar)
* 10.3 Panther
* 10.4 Tiger
* 10.5 Leopard
* 10.6 Snow Leopard
* 10.7 Lion
* OS X 10.8 Mountain Lion
* 10.9 Mavericks
* 10.10 Yosemite
* 10.11 El Capitan
* macOS 10.12 Sierra
* 10.13 High Sierra
* 10.14 Mojave
* 10.15 Catalina
* 11 Big Sur
* 12 Monterey
* 13 Ventura
* 14 Sonoma
* 15 Sequoia

Apple TV|

| Apple TV
Software|

* Derived from Mac OS X 10.4 Tiger: 1
* 2
* 3

* Derived from iOS 4–8: 4
* 5
* 6
* 7

tvOS|

* Derived from iOS 9–18: 9
* 10
* 11
* 12
* 13
* 14
* 15
* 16
* 17
* 18

iPhone,
iPod Touch|

| iPhone OS,
iOS|

* Derived from Mac OS X: iPhone OS 1
* 2
* 3

* iOS 4
* 5
* 6
* 7
* 8
* 9
* 10
* 11
* 12
* 13
* 14
* 15
* 16
* 17
* 18

iPad|

| iPhone OS,
iOS|

* Derived from Mac OS X: iPhone OS 3.2
iOS 4
* 5
* 6
* 7
* 8
* 9
* 10
* 11
* 12

|

iPadOS|

* Derived from iOS 13-18: 13
* 14
* 15
* 16
* 17
* 18

Apple Watch|

| watchOS|

* Derived from iOS 8–18: 1
* 2
* 3
* 4
* 5
* 6
* 7
* 8
* 9
* 10
* 11

|

Embedded|

| bridgeOS|

* Derived from watchOS: 1
* 2

|

HomePod|

| audioOS|

* Derived from iOS: 11
* 12
* 13
* Derived from tvOS:
* 13.4
* 14
* 15
* 16

|

Others|

* OpenDarwin
* PureDarwin

* macOS version history
* Mac OS X Server version history
* tvOS version history
* iOS version history
* iPadOS version history
* watchOS version history
* audioOS version history
Italics denote upcoming products

* v
* t
* e

macOS

* History
* Architecture
* Built-in apps
* Server
* Software

Versions|

| Mac OS X|

* Server 1.0
* Public Beta
* 10.0 Cheetah
* 10.1 Puma
* 10.2 Jaguar
* 10.3 Panther
* 10.4 Tiger
* 10.5 Leopard
* 10.6 Snow Leopard

|

OS X|

* 10.7 Lion
* 10.8 Mountain Lion
* 10.9 Mavericks
* 10.10 Yosemite
* 10.11 El Capitan

macOS|

* 10.12 Sierra
* 10.13 High Sierra
* 10.14 Mojave
* 10.15 Catalina
* 11 Big Sur
* 12 Monterey
* 13 Ventura
* 14 Sonoma
* 15 Sequoia

Applications|

| Core Applications|

* App Store
* Automator
* Calculator
* Calendar
* Chess
* Contacts
* Control Center
* Dictionary
* DVD Player
* FaceTime
* Finder
* Game Center
* Grapher
* Home
* Launchpad
* Mail
* Messages
* News
* Music
* Notes
* Notification Center
* Podcasts
* Photo Booth
* Photos
* Preview
* Quicktime Player
* Reminders
* Safari
* version history
* Shortcuts
* Siri
* Stickies
* TextEdit
* Time Machine

|

Developer Tools|

| Xcode|

* Instruments
* FileMerge

|

Former tools|

* Interface Builder
* Dashcode
* Quartz Composer

Former Applications|

* Dashboard
* Front Row
* iChat
* iPhoto
* iSync
* iTunes
* history
* Sherlock

Utilities|

* Activity Monitor
* AirPort Utility
* Archive Utility
* Audio MIDI Setup
* Bluetooth File Exchange
* Boot Camp
* ColorSync
* Configurator
* Console
* Crash Reporter
* Digital Color Meter
* Directory Utility
* DiskImageMounter
* Disk Utility
* Font Book
* Help Viewer
* Image Capture
* Installer
* Keychain Access
* Migration Assistant
* Script Editor
* System Settings
* System Information
* Terminal
* Universal Access
* VoiceOver

Discontinued|

* Grab
* Network Utility
* ODBC Administrator
* Remote Install Mac OS X
* Software Update

Technologies &
User Interface|

* AirDrop
* AppKit
* Apple File System
* Apple menu
* Apple Push Notification service
* AppleScript
* Aqua
* Audio Units
* AVFoundation
* Bonjour
* Bundle
* CloudKit
* Cocoa
* ColorSync
* Command key
* Core Animation
* Core Audio
* Core Data
* Core Foundation
* Core Image
* Core OpenGL
* Core Text
* Core Video
* CUPS
* Cover Flow
* Darwin
* Dock
* FileVault
* Fonts
* Foundation
* Gatekeeper
* Grand Central Dispatch
* icns
* iCloud
* Kernel panic
* Keychain
* launchd
* Mach-O
* Menu extra
* Metal
* Mission Control
* Night Shift
* OpenCL
* Option key
* Preference Pane
* Property list
* Quartz
* Quick Look
* Rosetta
* Smart Folders
* Speakable items
* Spotlight
* Stacks
* System Integrity Protection
* Uniform Type Identifier
* Universal binary
* WebKit
* XNU
* XQuartz

Deprecated|

* HFS+

Discontinued|

* BootX
* Brushed metal
* Carbon
* Classic Environment
* Inkwell
* QuickTime
* Spaces
* Xgrid

* Italics denote upcoming products.
* Category

* v
* t
* e

Operating systems by Apple

Apple II, III, Lisa|

* Apple II series
* Apple DOS
* ProDOS
* GS/OS
* Apple III
* SOS
* Lisa
* Lisa OS
* MacWorks

Mac|

| Classic Mac OS|

* System 1
* Systems 2, 3, and 4
* System 5
* System 6
* System 7
* Mac OS 8
* Mac OS 9

|

macOS|

* History
* NeXTSTEP
* OpenStep
* Rhapsody
* Public Beta
* Core
* Darwin
* XNU
* Desktop
* Mac OS X 10.0 (Cheetah)
* 10.1 (Puma)
* 10.2 (Jaguar)
* 10.3 (Panther)
* 10.4 (Tiger)
* 10.5 (Leopard)
* 10.6 (Snow Leopard)
* 10.7 (Lion)
* 10.8 (Mountain Lion)
* 10.9 (Mavericks)
* 10.10 (Yosemite)
* 10.11 (El Capitan)
* 10.12 (Sierra)
* 10.13 (High Sierra)
* 10.14 (Mojave)
* 10.15 (Catalina)
* 11 (Big Sur)
* 12 (Monterey)
* 13 (Ventura)
* 14 (Sonoma)
* 15 (Sequoia)
* Server
* Mac OS X Server 1.0

Other projects|

* Shipped
* A/ROSE
* A/UX
* AIX for Apple Network Servers
* MAE
* MkLinux
* PowerOpen Environment
* Cancelled
* Star Trek
* Taligent
* Copland
* Nukernel
* Vanguard

iPod, iPhone, iPad|

* iPod software
* iOS
* iPhone OS 1
* iPhone OS 2
* iPhone OS 3
* iOS 4
* iOS 5
* iOS 6
* iOS 7
* iOS 8
* iOS 9
* iOS 10
* iOS 11
* iOS 12
* iOS 13
* iOS 14
* iOS 15
* iOS 16
* iOS 17
* iOS 18
* iPadOS
* iPadOS 13
* iPadOS 14
* iPadOS 15
* iPadOS 16
* iPadOS 17
* iPadOS 18

Other devices|

* Newton
* Newton OS
* Apple Watch
* watchOS
* Apple TV
* Apple TV Software
* tvOS
* Apple Vision Pro
* visionOS
* visionOS 1
* visionOS 2
* HomePod
* audioOS
* T series
* bridgeOS

List •  Category

* v
* t
* e

Unix and Unix-like operating systems and compatibility layers

* Architecture
* Filesystem
* History
* Philosophy
* Security
* Shell

Operating
systems|

| BSD|

* 386BSD
* FreeBSD
* NetBSD
* OpenBSD
* DragonFly BSD
* NeXTSTEP
* Darwin
* macOS
* iOS
* audioOS
* iPadOS
* tvOS
* watchOS
* bridgeOS
* SunOS
* Ultrix

|

Linux|

* Android
* Arch
* ChromeOS
* Debian
* Fedora
* Gentoo
* Red Hat
* SUSE
* Ubuntu
* Other distributions

System V|

* A/UX
* AIX
* HP-UX
* IRIX
* OpenServer
* Solaris
* OpenSolaris
* Illumos
* Tru64 UNIX
* UnixWare

Other|

* Coherent
* Domain/OS
* GNU
* Hurd
* LynxOS
* Minix
* MOS
* OSF/1
* QNX
* BlackBerry 10
* Research Unix
* SerenityOS
* Xenix
* more...

Compatibility
layers|

* Cygwin
* Darling
* Eunice
* GNV
* Interix
* MachTen
* Microsoft POSIX subsystem
* MKS Toolkit
* PASE
* P.I.P.S.
* PWS/VSE-AF
* UNIX System Services
* UserLAnd Technologies
* Windows Services for UNIX
* Windows Subsystem for Linux

* Italics indicate discontinued systems.  Category
* Commons

* v
* t
* e

Free and open-source software

General|

* Alternative terms for free software
* Comparison of open-source and closed-source software
* Comparison of source-code-hosting facilities
* Free software
* Free software project directories
* Gratis versus libre
* Long-term support
* Open-source software
* Open-source software development
* Outline
* Timeline

Software
packages|

* Audio
* Bioinformatics
* Codecs
* Configuration management
* Drivers
* Graphics
* Wireless
* Health
* Mathematics
* Office suites
* Operating systems
* Routing
* Television
* Video games
* Web applications
* E-commerce
* Android apps
* iOS apps
* Commercial
* Formerly proprietary
* Formerly open-source

Community|

* Free software movement
* History
* Open-source-software movement
* Events
* Advocacy

Organisations|

* Free Software Movement of India
* Free Software Foundation

Licenses|

* AFL
* Apache
* APSL
* Artistic
* Beerware
* BSD
* Creative Commons
* CDDL
* EPL
* Free Software Foundation
* GNU GPL
* GNU AGPL
* GNU LGPL
* ISC
* MIT
* MPL
* Python
* Python Software Foundation License
* Shared Source Initiative
* Sleepycat
* Unlicense
* WTFPL
* zlib

| Types and
standards|

* Comparison of licenses
* Contributor License Agreement
* Copyleft
* Debian Free Software Guidelines
* Definition of Free Cultural Works
* Free license
* The Free Software Definition
* The Open Source Definition
* Open-source license
* Permissive software license
* Public domain
* Viral license

|

Challenges|

* Digital rights management
* License proliferation
* Mozilla software rebranding
* Proprietary device drivers
* Proprietary firmware
* Proprietary software
* SCO/Linux controversies
* Software patents
* Software security
* Trusted Computing

Related
topics|

* Forking
* GNU Manifesto
* Microsoft Open Specification Promise
* Open-core model
* Open-source hardware
* Shared Source Initiative
* Source-available software
* The Cathedral and the Bazaar
* Revolution OS

* Portal
* Category

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