Mac Versions

At WWDC 2025 (June 9, 2025), Apple jumped from macOS 15 (Sequoia) directly to macOS 26 (Tahoe) to align all of Apple's operating systems on a year-based version number tied to the September release calendar — iOS, iPadOS, watchOS, tvOS, visionOS, and audioOS all moved to "26" on the same release. The "26" represents September 2025 through September 2026.

• Liquid Glass — a system-wide visual rewrite using a new translucent material across the menu bar, Dock, sheets, sidebars, and app chrome. The largest Mac visual refresh since Big Sur in 2020, and the macOS half of the same redesign that landed on iOS 26.
• Year-based versioning across all Apple OSes: macOS 26 Tahoe, iOS 26, iPadOS 26, watchOS 26, tvOS 26, visionOS 26, audioOS 26.
• Apple Intelligence updates: Live Translation in Messages, FaceTime, and Phone (the latter via Continuity with iPhone Mirroring); deeper writing-tool integration system-wide.
• Spotlight redesigned around Apple Intelligence with on-device action surfacing.
• Continuity Camera Live Translation overlays on the Mac.
• Confirm latest point release against developer.apple.com.

• Apple Intelligence on supported Apple Silicon Macs (M1 and later) — writing tools, image generation, summarization, smarter Siri, and the OpenAI partnership for ChatGPT-backed Siri fallback. Features rolled out across 15.1 (Oct 2024) and 15.2 (Dec 2024).
• iPhone Mirroring — control your iPhone in a window on the Mac, drag files between the two.
• Native window tiling with keyboard and edge-drag affordances.
• Passwords app spun out of Settings into its own first-class application.
• Safari highlights and reader summarization powered by Apple Intelligence.
• Last release under the old `10.x` → `15` integer cadence; macOS 26 Tahoe (above) was the first under year-based versioning.

• Desktop widgets that fade back when an app comes to the foreground; iPhone widgets via Continuity.
• Game Mode prioritizes the running game's CPU/GPU access and reduces audio latency to controllers.
• Game Porting Toolkit — an evaluation environment based on Wine, CrossOver, and a D3D12-to-Metal translation layer (D3DMetal), shipped as developer tooling. Apple's most direct overture to Windows-game ports in twenty years.
• Presenter Overlay during video calls; Reactions in FaceTime.
• Web apps from Safari with their own dock icon and process.

• Stage Manager — a window-grouping multitasker. Polarizing on launch and refined repeatedly through point releases.
• Continuity Camera — use your iPhone as a high-quality webcam on the Mac.
• System Settings replaced System Preferences with an iOS-style settings list. Twenty-one years of muscle memory invalidated; widely complained about for the first six months.
• Mail scheduling, undo send, follow-up reminders.
• Passkeys synced via iCloud Keychain.

• Universal Control — one keyboard and mouse spans Mac and iPad with no setup. Shipped in 12.3 in March 2022 after a delay.
• Shortcuts arrives on Mac (the iOS automation app, ported via Catalyst).
• Live Text in images (gated to M1 in regions where the model is available).
• SharePlay over FaceTime.
• Focus modes, Quick Note, and Tags in Notes.

• First macOS to run on Apple Silicon. Shipped alongside the M1 MacBook Air, MacBook Pro 13", and Mac mini in November 2020.
• Version-number jump from 10.x to 11 — the first new major number since Mac OS X 10.0 in 2001.
• Largest visual refresh since OS X 10.10 Yosemite — new icon grid, redesigned Control Center, Notification Center as a unified panel.
• Rosetta 2 — Apple's ahead-of-time and JIT translation layer for Intel binaries on Apple Silicon. One-time install nag, then transparent.
• Signed system volume (SSV) — the system partition is cryptographically sealed and read-only.
• Native iPhone and iPad apps run unchanged on Apple Silicon Macs (developer-opt-in).

• 32-bit support removed entirely — the most disruptive single Mac release of the last decade for power users. Many older apps and games stopped running.
• iTunes split into Music, Podcasts, and TV apps after eighteen years.
• Sidecar — use an iPad as a second display, wired or wireless, with optional Pencil input.
• Mac Catalyst — ship a single iPad app codebase as a Mac app.
• Voice Control replaces the old Dictation flow with full hands-free system control.
• Read-only system volume on supported hardware (foreshadowing Big Sur's SSV).

• System-wide Dark Mode for the first time.
• Stacks on the Desktop — auto-grouped piles of files by kind/date/tag.
• Continuity Camera — pull a photo straight from iPhone into a document.
• News, Stocks, Voice Memos, and Home apps ported from iOS — the early Catalyst seed.
• Notarization API introduced for developer-signed apps distributed outside the Mac App Store.
• Last macOS to run 32-bit Intel apps — the cutoff is Catalina.

• APFS — the new copy-on-write filesystem — became the default for SSDs, replacing HFS+ after seventeen years.
• Metal 2 with VR support; native HEVC and HEIF.
• Refinement-focused release in the spirit of Snow Leopard, hence the name.
• Notable security flaw at launch: a "root" user could be enabled with no password (CVE-2017-13872), patched within days.

• "OS X" was rebranded to "macOS" for parity with iOS, watchOS, and tvOS.
• Siri on Mac.
• Auto Unlock with Apple Watch.
• Universal Clipboard, iCloud Drive Desktop and Documents sync.
• Apple Pay on the web (in Safari).
• Picture-in-Picture video.

• System Integrity Protection (SIP) — even root cannot modify protected system locations. The first major step in the lockdown progression.
• Split View — two apps side by side in full-screen.
• Metal arrives on Mac, alongside continued OpenGL support.
• Refinement focused, after Yosemite's redesign.

• Flat-and-translucent redesign aligning Mac visually with iOS 7's 2013 reset.
• Continuity — Handoff, AirDrop between Mac and iOS, iPhone calls answered on the Mac, hotspot tethering with one click.
• Spotlight gets a centered overlay and richer results.
• iCloud Drive launches.
• Phone-style notifications and a redesigned Today view.

• First California place name. The cat-name well had run dry — Apple shifted to California landmarks, a naming pattern that has held since.
• First free macOS upgrade. Every subsequent major has been free.
• Compressed memory, App Nap, and Timer Coalescing — battery-life-focused engineering work.
• Tabbed Finder windows, finally.
• iBooks and Maps ported from iOS.

• Gatekeeper — a developer-signing-and-distribution policy that lets users restrict launches to App Store and/or identified-developer code. The second major step in the lockdown progression.
• Notification Center, ported from iOS.
• iCloud document sync built into apps directly.
• Messages app replaces iChat, with iMessage support.
• AirPlay Mirroring to Apple TV.

• "Mac" was dropped from the brand — "Mac OS X" became "OS X" with this release.
• Mac App Store launches inside Lion (it had also been backported to Snow Leopard 10.6.6).
• Full-screen apps and Mission Control replace Spaces + Exposé.
• Launchpad — an iOS-style app grid for the desktop.
• Auto Save, Versions, and Resume across applications.
• FileVault 2 — full-disk encryption.
• First major distributed primarily as a Mac App Store download rather than a boxed DVD.

• Intel-only. Snow Leopard dropped PowerPC support entirely, completing the Intel transition that began with Tiger in 2006.
• Deliberately marketed as having "no new features" — the focus was on refinement, performance, and code-cleanup.
• Grand Central Dispatch — OS-level parallelism API.
• OpenCL — programmable GPGPU work.
• 64-bit kernel and applications fully across the system.
• The fondly-remembered release that long-time Mac users still cite as the high-water mark for stability.

• Time Machine — automatic incremental backups to a connected external drive, with the iconic "fly through space" restore UI.
• Spaces — multiple virtual desktops.
• Redesigned Dock with stacks; new translucent menu bar.
• Cover Flow Finder.
• Native ZFS support (read-only at launch, never finished after Sun's acquisition by Oracle).
• Last release to support both PowerPC and Intel Macs.

• Spotlight — the system-wide search index that has been the foundation of every Mac search experience since.
• Dashboard — HTML/JS widgets in an overlay layer.
• Automator — the "drag-and-drop scripting" surface that has quietly persisted.
• Core Image, Core Data, and Core Audio.
• Shipped in May 2005 on PowerPC; in January 2006 the first Intel Macs (iMac, MacBook Pro) shipped a binary-different build of Tiger as their initial OS, kicking off the Intel transition.

• Exposé — press F9/F10/F11 to fan-out, app-fan-out, or clear the desktop. Among the most copied UI ideas of the decade.
• Fast User Switching with the now-iconic rotating-cube animation.
• iChat AV — video chat over the public internet, ahead of mainstream alternatives.
• Brushed-metal Finder, FileVault home-folder encryption.

• First version where the codename became the marketing name. Every subsequent release through Sequoia has used a public, evocative place or animal name.
• Quartz Extreme — GPU-accelerated window compositing.
• iChat (AIM-compatible).
• Address Book, Inkwell handwriting, Universal Access (the precursor to today's Accessibility framework).
• Unveiled at WWDC 2002 in the keynote where Steve Jobs literally held a funeral on stage for Mac OS 9 — coffin, eulogy, and all.

• Free upgrade for buyers of 10.0 — an explicit acknowledgment that 10.0 had not been ready.
• Performance work across the board; DVD playback enabled.
• Many people consider this the real "1.0" of Mac OS X.
• Codenames Puma (10.1) and Cheetah (10.0) were internal-only at this point — the public marketing was simply "Mac OS X 10.1."

• The first commercial release of the NeXT-derived Mac OS X line.
• Aqua interface; Dock; protected memory and preemptive multitasking from the NeXT foundation.
• Required the "Classic" environment to run pre-Carbon legacy apps inside a Mac OS 9 sandbox.
• Slow on then-current hardware and incomplete on basics like DVD playback. Most users kept booting into Mac OS 9 for daily work for at least another year.

• Paid public beta. Apple charged $29.95 for the Public Beta CD — the only paid OS beta in the company's history.
• First public look at the Aqua interface; Dock; and the NeXT-foundation underpinnings.
• Time-bombed: the Public Beta stopped working in May 2001 to push users to the 10.0 release.

• Derived directly from Rhapsody — effectively NeXTSTEP / OPENSTEP with a Mac-flavored shell.
• Used the Platinum (Mac OS 8/9) appearance, not Aqua — Aqua arrived with the Public Beta a year and a half later.
• Shipped to a small audience of server administrators and developers.
• The first publicly purchasable product based on the NeXT foundation under the Mac brand.

• Developer-only seed releases shipped in 1997 (DR1) and 1998 (DR2).
• Two API stories: "Yellow Box" — the NeXT/OPENSTEP-derived APIs that became Cocoa; and "Blue Box" — a virtualized Mac OS 8 environment for legacy apps, the precursor to Classic.
• Reception from existing Mac developers was poor — rewriting in Yellow Box was a heavy lift.
• The strategy was reset at WWDC 1998: the Carbon API was added so existing Mac apps could be ported with far less work, and Mac OS X was renamed/rescoped from "Rhapsody for consumers" to a platform that would carry both Carbon and Cocoa apps.

• The final Classic Mac OS release, shipped after Mac OS X 10.1.
• Tuned for use as the host of Mac OS X's Classic environment so existing Mac apps could keep running on the new platform.
• Mac OS 9 was officially declared dead at WWDC 2002, where Steve Jobs delivered an on-stage funeral — coffin, eulogy, and "Dead Man's Curve" piped over the speakers — for the OS that had defined the Mac for eighteen years.

• Multi-user accounts — the Classic line's first real attempt at user separation.
• Keychain — password storage that has survived through every Mac OS X / macOS release since.
• Software Update — automatic OS patching.
• Marketed as "the best internet operating system ever," with iTools (the precursor to .Mac, MobileMe, and iCloud).
• Held in nostalgia by long-time Classic users as the last "real" Mac OS before the NeXT-derived rebuild.

• First Mac OS that required a PowerPC processor — ended support for the 68K Macs that had defined the brand from 1984 to 1994.
• Sherlock — a unified search across local files and the web; remembered fondly until Apple's acquisition of Karelia and the (separate, unrelated) "Sherlocking" controversy years later.
• Shipped a few months after the original iMac G3 in August 1998, which was Apple's first major hardware win in years.
• Themed Appearance support (used by ResEdit hackers more than by Apple itself).

• Platinum visual theme — the look that defined the late-Classic Mac.
• Contextual (right-click) menus, after a decade of single-button-mouse orthodoxy.
• Multithreaded Finder — copy a file in one window without freezing the rest of the desktop.
• Shipped only a few months after Steve Jobs returned to Apple via the NeXT acquisition. Repackaged some scoped-down Copland work alongside conventional 7.x improvements.
• Sold ~3 million copies in two weeks — Apple needed the cash badly at the time.

• First release officially branded "Mac OS" — previous releases had been "System 7.x."
• Renaming was tied to Apple's brief Mac-clone licensing era, in which third-party manufacturers (Power Computing, Motorola StarMax, UMAX, Daystar) shipped Macs running this OS.
• Steve Jobs ended the cloning program shortly after his return.

• Apple Menu Items — the user-customizable Apple Menu that survived nominally into recent macOS releases.
• Stickies, the desktop note app.
• Drag-and-drop pervasive across the system.
• Codename "Capone" was a reference to Microsoft Chicago (Windows 95) — "Capone is the gangster from Chicago."

• 32-bit clean (with caveats — many third-party apps had to be updated).
• Virtual memory built in — previously a third-party Connectix add-on.
• Color in the GUI by default; Aliases (the Classic counterpart to symbolic links).
• AppleScript — the system-wide scripting layer that has persisted for thirty-plus years.
• TrueType scalable fonts (jointly developed with Microsoft to escape Adobe's PostScript Type 1 licensing).
• Codename "Big Bang" — the first major Mac OS rewrite since 1984.

• Consolidated System 4 and System 5 fixes into a single coherent release.
• Color support on the then-new Mac II (six-bit, 256 colors).
• MacroMaker — the first bundled keystroke recorder.
• The longest-lived of the early Systems — many users stayed on it until well after System 7's release.

• MultiFinder — the cooperative-multitasking shell — was bundled by default for the first time.
• Briefly transitional; the line moved on quickly to System 6.

• Optional MultiFinder shell let users run more than one app at a time on the Mac for the first time.
• Cooperative multitasking only — preemptive scheduling waited for Mac OS X.
• Targeted at the Mac II (the first color, expandable Mac, also released in 1987).

• HFS (Hierarchical File System) replaced the original MFS (Macintosh File System), introducing real folder hierarchies on the Mac for the first time.
• HFS persisted until APFS replaced it in 2017 — thirty-one years.

• Bundled with the LaserWriter and the AppleTalk networking stack.
• Minor system-software refresh on top of the original 1984 release.

• Shipped on the original 128K Macintosh, announced January 24, 1984 — two days after the famous "1984" Super Bowl ad.
• The OS itself fit in ROM and a 400KB single-sided floppy. No hard drive on the original hardware.
• Single-tasking, single-user. The Finder was a separate application, not a continuously running shell.
• Core engineering and design from Andy Hertzfeld, Bill Atkinson, Bruce Horn, Susan Kare, and Burrell Smith. Folklore.org has the definitive primary-source archive.