The following is a list of operating systems released by Apple Inc. As of 2023, there are six supported software platforms: iOS, iPadOS, watchOS, tvOS, macOS and visionOS.

Prior to the introduction of the Macintosh in early 1984, Apple had several operating systems for the Apple II series, Apple SOS for the Apple III series, and Lisa OS and MacWorks XL for the Apple Lisa series; those were introduced between 1977 and 1983.

The original operating system for the Macintosh was the classic Mac OS, which was introduced in early 1984 as System Software. In 1997, System Software was renamed Mac OS.

In 1999, Mac OS X Server 1.0 was released, followed by Mac OS X 10.0, the first consumer release of the Mac OS X.

From the release of Mac OS X 10.0 until early 2007, Mac OS X was the only software platform. In early 2007, iPhone OS was introduced, increasing the number of software platforms by one, from one to two. In 2010, iPhone OS was renamed iOS. In 2011, Mac OS X was renamed OS X. In early 2015, the number of software platforms rose by one, from two to three, as watchOS was introduced. In late 2015, tvOS was introduced, increasing the number of software platforms again by one, from three to four. In 2016, OS X was renamed macOS. In 2019, iPadOS was introduced as the derived version of iOS for iPad, increasing the number of software platforms again by one, from four to five. In 2020, macOS received an increment in its version, from 10 to 11. In 2023, the number of software platforms rose again by one, from five to six, as visionOS was introduced.^{[citation needed]}

• Apple DOS is the first operating system for Apple computers.^[1]
• Apple ProDOS
• Apple GS/OS

• Apple SOS

• Lisa OS
• MacWorks XL

• System 1
• System 2
• System 3
• System 4
• System Software 5 – also marketed as System 5
• System Software 6 – also marketed as System 6
• System 7 – System 7.5.1 was the first to refer to itself as Mac OS, Mac OS 7.6 was the first to be branded as "Mac OS"
• Mac OS 8
• Mac OS 9 – Mac OS 9.2.2 was the last version of Classic Mac OS

macOS was initially called Mac OS X and later OS X.

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

macOS Server was initially called Mac OS X Server and later OS X Server.

• Mac OS X Server 1.0 – code name Hera, also referred to as Rhapsody
• Mac OS X Server 10.0 – code name Cheetah
• Mac OS X Server 10.1 – code name Puma
• Mac OS X Server 10.2 – code name Jaguar
• Mac OS X Server 10.3 – code name Panther
• Mac OS X Server 10.4 – code name Tiger
• Mac OS X Server 10.5 – also marketed as Leopard Server
• Mac OS X Server 10.6 – also marketed as Snow Leopard Server

Starting with Lion, there is no separate Mac OS X Server operating system. Instead the server components are a separate download from the Mac App Store.

• Mac OS X Lion Server – 10.7 – also marketed as OS X Lion Server
• OS X Mountain Lion Server – 10.8 – also marketed as Mountain Lion Server
• OS X Mavericks Server – 10.9 – also marketed as Mavericks Server
• OS X Yosemite Server – 10.10 – also marketed as Yosemite Server 4.0
• OS X 10.11 Server 5.0 – also marketed as OS X Server 5.0
• OS X 10.11 Server 5.1 – also marketed as OS X Server 5.1
• macOS 10.12 Server 5.2 – also marketed as macOS Server 5.2
• macOS 10.12 Server 5.3 – also marketed as macOS Server 5.3
• macOS 10.13 Server 5.4 – also marketed as macOS Server 5.4
• macOS 10.13 Server 5.5 – also marketed as macOS Server 5.5

• bridgeOS – powers the Touch Bar and other internal components
• NeXTSTEP
• OPENSTEP
• Darwin

• A/ROSE
• A/UX
• AIX for Apple Network Servers
• Macintosh Application Environment
• MkLinux
• PowerOpen Environment
• Star Trek – unreleased
• Taligent – unreleased
• Copland – unreleased

• Newton OS

• iPod OS

iOS was previously known as iPhone OS, despite also being available on the iPod Touch (1st, 2nd, and 3rd generations) and the original iPad.

• iPhone OS 1 – derived from "Mac OS X" (now known as "macOS")
• iPhone OS 2
• iPhone OS 3
• iOS 4 – continued from iPhone OS 3
• 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

At its June 2019 Worldwide Developer Conference, Apple introduced iPadOS, a version of iOS, for iPad tablets, promised for fall 2019 release.^[2][3]

• iPadOS 13 – derived from iOS 13
• iPadOS 14 – derived from iOS 14
• iPadOS 15 – derived from iOS 15
• iPadOS 16 - derived from iOS 16
• iPadOS 17 - derived from iOS 17
• iPadOS 18 - derived from iOS 18

• watchOS 1 – derived from iOS 8
• watchOS 2 – derived from iOS 9
• watchOS 3 – derived from iOS 10
• watchOS 4 – derived from iOS 11
• watchOS 5 – derived from iOS 12
• watchOS 6 – derived from iOS 13
• watchOS 7 – derived from iOS 14
• watchOS 8 – derived from iOS 15
• watchOS 9 – derived from iOS 16
• watchOS 10 – derived from iOS 17
• watchOS 11 – derived from iOS 18

• Apple TV Software 1 – derived from Mac OS X 10.4 Tiger
• Apple TV Software 2 – derived from Mac OS X 10.4 Tiger
• Apple TV Software 3 – derived from Mac OS X 10.4 Tiger
• Apple TV Software 4 – derived from iOS 4 and iOS 5
• Apple TV Software 5 – derived from iOS 5 and iOS 6
• Apple TV Software 6 – derived from iOS 7
• Apple TV Software 7 – derived from iOS 8

There was no Apple TV Software 8; version 8 was skipped when moving to tvOS.

• tvOS 9 – derived from iOS 9
• tvOS 10 – derived from iOS 10
• tvOS 11 – derived from iOS 11
• tvOS 12 – derived from iOS 12
• tvOS 13 - derived from iOS 13
• tvOS 14 - derived from iOS 14
• tvOS 15 - derived from iOS 15
• tvOS 16 - derived from iOS 16
• tvOS 17 - derived from iOS 17
• tvOS 18 - derived from iOS 18

• visionOS 1 - derived from iOS 17
• visionOS 2 - derived from iOS 18