Reprinted from TidBITS by permission; reuse governed by Creative Commons license BY-NC-ND 3.0. TidBITS has offered years of thoughtful commentary on Apple and Internet topics. For free email subscriptions and access to the entire TidBITS archive, visit http://www.tidbits.com/ Apple Operating Systems Jump to 26? Adam Engst It's no secret that Apple's operating system version numbering has evolved organically. The company currently maintains seven operating systems with version numbers that begin with four different integers (macOS 15, iOS 18, watchOS 11, and visionOS 2), although they share so much underlying code that they tend to move together with decimal updates. That's why I've started relying on shorthand in article titles like 'Apple Releases iOS 18.5, macOS 15.5, and Other x.5 OS Updates' and tightening it even further to 'OS x.5' in issue titles. Happily, the current numbering mess may soon be a thing of the past. At Bloomberg,[1]Mark Gurman reportsthat Apple plans to identify the next versions of all its operating systems by year rather than by version number. If his information is accurate, we'll see macOS 26, iOS 26, iPadOS 26, and so on, which should make it much easier for us to keep track and trivial to remember when each version was current. The OS 26 updates are likely to be released toward the end of 2025, so these new version numbers are looking ahead to next year. Unsurprisingly, Apple declined to comment on the report, which also suggests that the new operating systems will share a user interface refresh. Version numbers based on years are nothing new in the software industry, but they often ran into problems when it came to shipping annual updates, making names feel outdated after a year or two. Adobe's[2]Illustrator 88 name(which was actually version 1.6) was a short-lived experiment, coming as it did between versions 1.1 and 2.0. Microsoft faced issues with the gaps between[3]Windows 95, Windows 98, and Windows 2000before transitioning to Windows Me and Windows XP. Eventually, Microsoft reverted to numbers with Windows 7, and now we're at Windows 11. Apple dabbled with year numbers for the[4]iWorkand[5]iLifebundles but stuck with standard version numbers for the individual apps. Given Apple's consistency in releasing major operating system versions every year since 2007 for iOS and 2012 for macOS, I doubt we will find ourselves in a situation where a major version remains current beyond its designated year. While it may not immediately benefit those of us who regularly need to reference older versions of Apple's operating systems, the annual numbering will gradually simplify locating each subsequent upgrade on the overall timeline. If you're curious, as I was, here's how we got to where we are now: * macOS 15:After many years of[6]macOS versionsincrementing a decimal number from 10.1 to 10.15 (forcing incremental releases within those larger versions to use a third number), Apple finally made an integer leap with macOS 11. Although the macOS names make them easier to discuss, with 7 big cat names and 12 California names, it's becoming increasingly difficult to remember which name corresponds to which number. * iOS 18:The macOS numbers don't align with the[7]iOS versions, as we're now at iOS 18. Version numbering for iOS has remained consistent throughout its history, with only an early name change from iPhone OS 3 to iOS 4. * iPadOS 18:When Apple split iPadOS from iOS in 2019, it kept the version number, so the first version was iPadOS 13. Subsequent[8]iPadOS versionshave remained in lockstep with iOS. * tvOS 18:Similar to iOS, tvOS experienced a name change and a numerical update when it transitioned from Apple TV Software 7 to tvOS 9. According to Wikipedia's descriptions, Apple based several versions of Apple TV Software on two versions of iOS, resulting in a discrepancy where Apple TV Software 6 was based on iOS 7. Following the name change,[9]tvOS versionshave aligned with iOS. * watchOS 11: With watchOS, Apple started from scratch with the first release in 2015. Since Apple introduced the Apple Watch Series 1 with the second-generation Apple Watch, the hardware numbers have trailed the [10]watchOS versions by one, with the Apple Watch Series 10 shipping alongside today's watchOS 11. * HomePod Software 18:Although it's internally referred to as audioOS, the public name of the HomePod's operating system is HomePod Software. Initially, Apple didn't distinguish it from iOS, with the HomePod Software name arriving mid-cycle with HomePod Software 13.4. Since then,[11]HomePod Software versionshave tracked with iOS. * visionOS 2:The 2024 release of the Apple Vision Pro introduced Apple's latest operating system, visionOS, and the company once again opted to start[12]visionOS versionsfrom 1. We'll see if this naming change comes to pass at WWDC in just a few weeks (see '[13]WWDC 2025 Scheduled for June 9'13,' 25 March 2025). Fingers crossed! References 1. https://www.bloomberg.com/news/articles/2025-05-28/apple-to-rebrand-device-operating-systems-ios-26-macos-26-watchos-26 2. https://guidebookgallery.org/splashes/illustrator 3. https://en.wikipedia.org/wiki/Microsoft_Windows#Timeline_of_releases 4. https://en.wikipedia.org/wiki/IWork#Major_releases 5. https://en.wikipedia.org/wiki/ILife#Releases_and_history 6. https://en.wikipedia.org/wiki/MacOS_version_history#Releases 7. https://en.wikipedia.org/wiki/IOS_version_history 8. https://en.wikipedia.org/wiki/IPadOS 9. https://en.wikipedia.org/wiki/TvOS#Version_history 10. https://en.wikipedia.org/wiki/WatchOS#Version_history 11. https://support.apple.com/en-us/108045 12. https://en.wikipedia.org/wiki/VisionOS#Version_history 13. https://tidbits.com/2025/03/25/wwdc-2025-scheduled-for-june-9-13/ .