On 24 March 2021, Mac OS X (now simply Mac OS) turned 20, as its first major release, Mac OS X 10.0 Cheetah was released on 24 March 2001. The denomination Mac OS X is however slightly older than that, as it debuted with the release of Mac OS X 1.0 Server on 16 March 1999.

Since my day job has kept me rather busy these past weeks, I haven’t been as prompt as other tech writers in recognising this 20-year milestone and writing something celebratory about it.

In this overview, then, I want to go through every major release of Mac OS X, and briefly talk about which new features I’ve liked the most for each release, and which features I was sad to see removed. I think that this approach is also a nice way to reminisce a bit about Mac OS X through the years. (Note that the features I liked the most may not necessarily coincide with important features that were added in each new release).

Before we begin: for practical reasons I’ve heavily relied on Wikipedia as a source of information, simply because there are too many details I can’t just recall by memory. The specific bits of information taken verbatim from Wikipedia are marked with [W].

If you have time and want a more detailed read on the history and evolution of Mac OS X, I strongly suggest checking out this article by John Siracusa and all the links to his monumental Mac OS X reviews and retrospectives listed therein. Siracusa’s contributions on the matter are a marvellous, immense endeavour deserving the highest praise.

Mac OS X 10.0 Cheetah

Released: 24 March 2001
Latest release: 10.0.4 — 22 June 2001
Wikipedia entry: here

I published a brief visual tour of Mac OS X 10.0.3 on my System Folder blog back in 2008.

I didn’t use 10.0 much at the time of its release. I was still using Mac OS 8.6 on my G3 iMac, and a friend gave me the 10.0 CD-ROM only in late July 2001, and when Mac OS X 10.1 Puma was released two months later, I upgraded immediately.

Features I liked the most:

• The Aqua interface: I really loved all the previous Macintosh user interfaces, and while other long-time Mac users weren’t particularly thrilled by the Aqua redesign at the time, I had no problems accepting the new look.
• Docklings: A very short-lived feature, but I liked it. In my afore-linked Tour of Mac OS X 10.0.3, I wrote: ‌Apple quickly abandoned the use of docklings, but at this time it seems pretty evident that the Dock was designed to be a versatile centre of operations, acting as a Launcher, a navigational tool (by putting folder aliases on the right side of it), an application switcher (taking the function of the Application menu in the Mac OS ‘classic’ Finder) but also as an evolution of the Control Strip. By the way, the ‘dockling’ concept wasn’t that bad. With hindsight, using the Dock for status icons could have been a better idea, since the Dock is more expandable and eventually has more room for icons rather than the menu bar.
• Protected memory: Memory protection so that if an application corrupts its memory, the memory of other applications will not be corrupted. [W]

Mac OS X 10.1 Puma

Released: 25 September 2001
Latest release: 10.1.5 — 6 June 2002
Wikipedia entry: here

I have memories of Puma as being a very stable release, especially in its last 10.1.5 iteration, and a real performance boost compared with 10.0. It stayed on my G3 iMac until the computer died in early 2003, and then it stayed on my iBook G3 SE FireWire until the release of Mac OS X 10.3 Panther. When I purchased my 12-inch PowerBook G4 in 2004, I installed Panther on it and downgraded the iBook to Mac OS X 10.2 Jaguar (Server) for some time, as I needed a machine with server functionalities.

Features I liked the most:

• Easier CD and DVD burning: better support in Finder as well as in iTunes. [W]
• DVD playback support: DVDs can be played in Apple DVD Player. [W] Fun fact: My iBook G3 SE Firewire was basically the first DVD player I’ve ever owned. I didn’t have a TV at the time, so I used the iBook to watch films, obviously connecting it to an external 17-inch display!
• The new Image Capture app: For me, Image Capture is and remains Mac OS’s true unsung hero. I’ve used it for years to import photos from my iOS devices connected to the Mac via cable. I generally let photos accumulate on my iPhones, then I periodically perform a mass import on my Mac and a subsequent purge on the iPhone, to free up some space. Image Capture is very fast at importing and/or deleting hundreds of iPhone photos.

Mac OS X 10.2 Jaguar

Released: 23 August 2002
Latest release: 10.2.8 — 3 October 2003
Wikipedia entry: here

Worth mentioning:

Mac OS X Jaguar introduced many new features to the Mac OS that remain to this day, including MPEG‑4 support in QuickTime, Address Book, and Inkwell for handwriting recognition. It also included the first release of Apple’s Zeroconf implementation, Rendezvous (later referred to as Bonjour), which allows devices over a network to discover each other and display available services to the user, such as file sharing, shared scanners, and printers. [W]

Features I liked the most:

• The new iChat app: Before iChat I used multiple other IM applications, which I always found lacking, especially UI-wise. I was glad to be able to use a single well-designed app to manage different IM protocols.
• All the improvements to the system UI.

Features I was sad to see removed:

• The famous Happy Mac that had greeted Mac users for almost 18 years during the Macintosh startup sequence was replaced with a large grey Apple logo with the introduction of Mac OS X Jaguar. [W]

Mac OS X 10.3 Panther

Released: 24 October 2003
Latest release: 10.3.9 — 15 April 2005
Wikipedia entry: here

Panther was the first Mac OS X version I got in line to purchase on launch day. At the time a group of friends owned an Apple Authorised Reseller in Milan, Italy, and they too set up a Night of the Panther event on 24 October 2003. With the purchase of a copy of Panther, among other things I was given a mousepad with the Panther ‘X’ logo. I still have that mousepad and I use it with my Power Mac G4 Cube.

Features I liked the most:

• Exposé: Helps the user manage windows by showing them all as thumbnails. [W]
• TextEdit’s compatibility with Microsoft Word .doc files.
• The new Font Book app: Apple’s own font manager, although I kept using Linotype FontExplorer X for a long time.
• Fast User Switching: Allows a user to remain logged in while another user logs in. [W]
• Safari: Last but not least, Safari. It seems incredible that Apple’s own browser is 18 years old now. While at the time my absolute favourite browser was Camino (which I had been using since its early versions, when it was still called Navigator first, then Chimera), Safari quickly became my second browser, replacing any other alternative browser I was using back then (like Internet Explorer and Opera).

Mac OS X 10.4 Tiger

Released: 29 April 2005
Latest release: 10.4.11 — 14 November 2007
Wikipedia entry: here

Tiger and 10.6 Snow Leopard are my absolute favourite releases in all Mac OS X history. I still have and use several PowerPC Macs running 10.4 Tiger, even a PowerBook G3/400 ‘Lombard’ which officially supports up to 10.3 Panther. The last Tiger minor release, 10.4.11, is just rock solid, and makes using older PowerPC machines a joy.

Features I liked the most:

• Spotlight: The then-new full-text and metadata search engine. In my opinion, this first version of Spotlight still has the best user interface, which started to degrade since Mac OS X 10.5 Leopard.
• The addition of RSS support in Safari: The new Safari 2.0 web browser in Mac OS X 10.4 Tiger features a built-in reader for RSS and Atom web syndication that can be accessed easily from an RSS button in the address bar of the web browser window. [W]
• Dashboard: A new mini-applications layer based on HTML, CSS, and JavaScript, which returns the desk accessories concept to the Mac OS. These accessories are known as widgets. It comes with several widgets such as Weather, World Clock, Unit Converter, and Dictionary/Thesaurus. More are available for free online. Its similarity to the Konfabulator application caused some criticism. [W] I really used and enjoyed Dashboard a lot, especially during the first years, then my usage gradually waned around maybe the 10.8 Mountain Lion era.
• The new Dictionary app: Very handy for a writer and translator as myself, also because it’s not dependent on an Internet connection to work (unless you use it to also look up things on Wikipedia). I remember thinking it was about time it debuted on Mac OS X, since even NeXTSTEP had a Digital Webster app back in 1988.
• The Unified window theme for the system UI: I’m probably one of the few long-time Mac users who liked the ‘Brushed Metal’ system interface in Mac OS X 10.3 Panther, but the new so-called Unified theme that debuted in Tiger was a huge improvement.

Mac OS X 10.5 Leopard

Released: 26 October 2007
Latest release: 10.5.8 — 13 August 2009
Wikipedia entry: here

Features I liked the most:

• Quick Look: A framework allowing documents to be viewed without opening them in an external application; and they can also be previewed in full screen. Plug-ins are available for Quick Look so that you can also view other files, such as Installer Packages. [W] For me, QuickLook is such a monumental feature in Mac OS X, and it’s the single feature I miss most when using Macs running previous releases or other operating systems that don’t have a similar feature. Hitting spacebar to preview anything is such an ingrained shortcut in my muscle memory.
• Back to My Mac: A feature for MobileMe users that allows users to access files on their home computer while away from home via the internet. [W] I really loved the concept, but sadly it never worked reliably for me.
• Boot Camp: A software assistant allowing for the installation of other operating systems, such as Windows XP (SP2 or later) or Windows Vista, on a separate partition (or separate internal drive) on Intel-based Macs. [W] At the time I had no real interest for this feature, as I was firmly Mac-only. Today, this feature allows me to boot my iMac in Windows 10 when needed, and it’s very very handy. (Although it’s still a pain if you want to install Windows on an external drive.)
• Spaces: An implementation of virtual desktops (individually called “Spaces”), it allows multiple desktops per user, with certain applications and windows in each desktop. The auto-switching feature in Spaces has annoyed some of its users. Apple added a new preference in 10.5.2 which disabled this feature, but there were still bugs found while switching windows. In 10.5.3, this problem was addressed and was no longer an issue. [W] As someone who typically works with a lot of open apps and documents, this feature was really an improvement (when it got stabilised in 10.5.3).
• Time Machine: Apple’s automated backup utility. I’m probably the only Mac user out there who (touches wood) never had a backup issue with Time Machine. It’s not my only backup solution, of course, but it did save my butt on more than one occasion.
• The addition of Reader mode in Safari 5: It removes formatting and ads from webpages, allowing for distraction-free reading. The technology was based on Arc90’s Readability.

Features I was sad to see removed:

• The Classic Environment — a hardware and software abstraction layer in PowerPC versions of Mac OS X that allows most legacy applications compatible with Mac OS 9 to run on Mac OS X — was removed in Leopard. I knew it had to happen at some point, and I was frankly surprised it had lasted this long, indeed a very generous grace period for those users still relying on Mac OS 9 applications. But still, I was sad to see it go.

Mac OS X 10.6 Snow Leopard

Released: 28 August 2009
Latest release: 10.6.8 v1.1 — 25 July 2011
Wikipedia entry: here

In case you missed it, I recently wrote a retrospective look at Mac OS X Snow Leopard in two parts:

• Part 1
• Part 2

Features I liked the most:

• I just liked this Mac OS X release as a whole, especially the improvements in the Finder (now rewritten in Cocoa), Safari 4, iChat, Time Machine.
• All the UI refinements. I talk about some of the most important in the aforementioned retrospective.

Features I was sad to see removed:

• Dropped support for AppleTalk.
• Dropped support for creating/updating HFS (also called Mac OS Standard) volumes.

Mac OS X 10.7 Lion

Released: 20 July 2011
Latest release: 10.7.5 — 4 October 2012
Wikipedia entry: here

Lion was the first Mac OS X release I truly wondered whether to install or not, and actively delayed upgrading until version 10.7.2 or 10.7.3. As you can read in the linked Wikipedia entry, reception for Mac OS X Lion was mixed, and I remember reading some negative first impressions by people I trusted. At the time it seemed like a downgrade compared to the stability of Snow Leopard.

Lion is also the Mac OS X version that introduced natural scrolling, where scrolling is reversed by default, to act more like a touch screen device, so that content moves in the direction of finger movement on trackpad or mouse (with the scrollbar moving in the opposite direction), rather than the scrollbar moving in the direction of finger movement (with the content moving in the opposite direction). [W]

I always found this to be ‘unnatural scrolling’, so I always reverted to the old way.

Features I liked the most:

• AirDrop: Lion-to-Lion direct file sharing via Wi-Fi Direct, with no wireless access point required. [W] At the time I didn’t have much use for AirDrop, but it has become much more reliable now, and I’m glad Apple introduced it.
• Auto Save: The Auto Save feature for application documents was a love/hate relationship for me. As Wikipedia says, it significantly alters traditional workflow patterns and is a controversial addition to the system. But I still think adding it was a good idea overall.
• System-wide support for full-screen apps.
• High-quality multilingual speech voices: I’ve always used text-to-speech to help me proofread my articles and anything I write, really. Since Lion, the high-quality UK female voice ‘Serena’ is firmly set as my default Speech voice. I love it.
• Improvements in TextEdit: The app gains a new graphical toolbar with font selection and text highlighting. [W]
• Resume feature: Applications resume in the same state when re-opened as already seen in iOS. [W]

Features I was sad to see removed:

• Save As: I always preferred to have this rather than Duplicate/Revert, and I remember having a hard time getting accustomed to the new workflow.
• Rosetta: The software that makes possible the execution of PowerPC software on x86 hardware was removed in Lion. I knew Apple would drop support for PowerPC apps at some point. And like with the removal of the Classic Environment in Leopard, I was surprised PowerPC support lasted this long in the first place. However at the time I was still relying on a few PowerPC apps and it was a bit annoying to find alternatives and adjust. But, as I said, I couldn’t expect PowerPC support to last forever…
• Removal of Intro videos: I don’t know you, but I loved the Welcome to Mac OS X videos playing after installing Mac OS X. I was sad Apple stopped making them.
• Removal of scrollbar arrows: This irked me. Even if scrolling became more precise; even if scrolling can be performed in finer increments by using the ↑ and ↓ keys, I still miss the scrollbar arrows.

OS X 10.8 Mountain Lion

Released: 25 July 2012
Latest release: 10.8.5 — 13 August 2015
Wikipedia entry: here

Mountain Lion was the first Mac OS X release to drop ‘Mac’ from its name, as Apple started referring to it as OS X Mountain Lion rather than Mac OS X Mountain Lion.

It was also the first release to be distributed in a completely digital format. (Its predecessor, too, was initially only available via a software download, but Apple later made it also available via a USB flash drive that could be purchased on the online Apple Store for $69).

Mountain Lion introduced a lot of new things on the Mac, mostly features borrowed from iOS and features that improved synchronisation between Mac OS and iOS — but these did little to really improve my workflow, so I won’t mention these in my ‘Features I liked most’ list.

I wasn’t particularly excited about Notification Centre on the Mac, for example. I hated that its icon replaced the Spotlight icon in the top right corner of the screen.

• Adding the Notes app to the Mac made sense, but since I was using (and still use) Simplenote + Notational Velocity or the more feature-rich nvALT, this addition didn’t really do anything for my workflow or sync habits.
• Mountain Lion is the OS X release that replaced iChat with Messages, and I’ve always liked iChat’s UI more.
• The updated Safari 6 added two features I liked (iCloud tabs and the unified smart search field), but dropped a featured I loved — RSS support (it was also dropped in Mail).
• Power Nap was another welcome feature. From Wikipedia: ‌Power Nap allows flash storage-based Macintoshes (late 2010 MacBook Air and later, or the MacBook Pro with Retina display) to synchronise with iCloud (Reminders, Calendars, Photo Stream, Notes, Mail, and Find My Mac) while sleeping and also allows a Mac to download App Store and OS X updates as well as make periodic Time Machine backups when it is plugged in and sleeping.

Mountain Lion was generally considered to be an improvement over Lion, especially in the UI department, and it did change a lot of stuff (as you can read on the linked Wikipedia entry). However, in retrospective, for me personally 10.8 is perhaps one of the least memorable OS X versions. I really needed to check Wikipedia for an overview of all the changes and improvements because off the top of my head I couldn’t recall any of them, except maybe Notification Centre. It’s ultimately a good thing, because it means that Mountain Lion worked flawlessly and reliably on my Macs.

OS X 10.9 Mavericks

Released: 22 October 2013
Latest release: 10.9.5 — 18 July 2016
Wikipedia entry: here

OS X Mavericks was the first OS X major release to be a free upgrade, and the first release to inaugurate using California locations instead of felines in OS X version codenames.

Features I liked the most:

• Timer coalescing: A feature that enhances energy efficiency by reducing CPU usage by up to 72 percent. This allows MacBooks to run for longer periods of time and desktop Macs to run cooler. [W]
• iCloud Keychain: I loved the idea, but I never activated this feature on my devices due to my implicit distrust in iCloud services; a distrust that lasts to this day despite the clear improvements over time.
• The new iBooks app: Maybe it’s just me, but I don’t mind reading or consulting books on my Macs.

Among the features I was sad to see removed there’s everything mentioned in the Wikipedia entry, i.e.:

• The Open Transport API has been removed.
• USB syncing of calendar, contacts and other information to iOS devices has been removed, instead requiring the use of iCloud.
• QuickTime 10 no longer supports many older video codecs and converts them to the ProRes format when opened. Older video codecs cannot be viewed in Quick Look.
• Apple also removed the ability to sync mobile iCloud Notes if iOS devices were upgraded from iOS 8 to iOS 9.

OS X 10.10 Yosemite

Released: 16 October 2014
Latest release: 10.10.5 — 19 July 2017
Wikipedia entry: here

As the Wikipedia entry says, Yosemite introduced a major overhaul of OS X’s user interface, emphasising flat graphic design over skeuomorphism, following the æsthetic introduced with iOS 7. It is the first major redesign of the OS X user interface since 10.5 Leopard. Other changes include thinner fonts and blurred translucency effects. Some icons have been changed to correspond with those of iOS 7 and iOS 8.

Unlike many other long-time Mac users, I really didn’t mind the UI redesign and the general flat æsthetic introduced in Yosemite. But the replacement of Lucida Grande with Neue Helvetica as system font was really a bad idea (I wrote some of my concerns in this article that predates WWDC 2014). That, the awful network instability (remember the discoveryd fiasco?), and other issues truly put me off, so Yosemite was the first Mac OS X version I refused to upgrade to, and I stayed on 10.9 Mavericks until 10.11 El Capitan was released.

Features I liked the most:

• The redesigned Dock: Its look was now more similar to the one in early Mac OS X versions up to Tiger.
• Continuity and Handoff: The Handoff functionality allows the operating system to integrate with iOS 8 devices over Bluetooth LE and Wi-Fi; users can place and answer phone calls using their iPhone as a conduit, send and receive text messages, activate personal hotspots, or load items being worked on in a mobile app (such as Mail drafts or Numbers spreadsheets) directly into their desktop equivalent. [W]

Features I was sad to see removed:

• Above all, the introduction of Photos as a replacement for both iPhoto and Aperture. I didn’t care much for iPhoto. I actually think that Photos is, overall, a better app than iPhoto ever was. But I’m still mad that Aperture was discontinued. It is still my professional photo editing and photo management app of choice, though. I like its workflow much better than, say, Adobe Lightroom’s.

OS X 10.11 El Capitan

Released: 30 September 2015
Latest release: 10.11.6 — 9 July 2018
Wikipedia entry: here

Overall a very stable system, especially in its last 10.11.6 release, that has never given me a single problem on my 2009 MacBook Pro.

Features I liked the most:

• The San Francisco font, thankfully replacing Neue Helvetica as system font.
• Window management features (see Wikipedia entry).

Mac OS 10.12 Sierra

Released: 20 September 2016
Latest release: 10.12.6 — 26 September 2019
Wikipedia entry: here

With the release of 10.12 Sierra, the ‘X’ is dropped from the name, and ‘Mac’ returns, although spelt as ‘macOS’. Quoting Wikipedia, the name “macOS” stems from the intention to uniform the operating system’s name with that of iOS, watchOS and tvOS. I have always refused to conform to such silly spelling, so you’ll always find it written as ‘Mac OS’ here and on my social media posts.

I haven’t much to say about Sierra. Like Yosemite, it’s a version I skipped altogether. Unlike Yosemite, I did not skip Sierra purposefully and I have nothing against it. At the time it was released, my mid-2009 MacBook Pro couldn’t be updated past El Capitan, and I didn’t want to use a third-party patch to update it to Sierra at all costs. When I finally got a new iMac in 2018, it came with Mac OS 10.13 High Sierra preinstalled.

Among the new features introduced in Sierra, worth mentioning are Siri and Night Shift. But the former has always been useless to me, and to the latter I’ve always preferred f.lux.

Mac OS 10.13 High Sierra

Released: 25 September 2017
Latest release: 10.13.6 (Security Update 2020-006) — 12 November 2020
Wikipedia entry: here

Perhaps my favourite Mac OS version in recent times. After a bit of a rocky start (see Problems on the Wikipedia entry), I find 10.13.6 to be a very stable environment that is virtually issue-free for me. I still use High Sierra on my 2017 21.5‑inch 4K retina iMac and on my mid-2013 11-inch MacBook Air. I’m considering updating both to 10.14 Mojave, but I’m not in a hurry, honestly.

Notable in High Sierra is that it’s the Mac OS release where the new APFS filesystem (replacing HFS+) is the default. Since my iMac has an internal hard drive and not an SSD, its filesystem is still HFS+, as High Sierra doesn’t force the change on internal hard drives. As I’m told, Mojave does update them to APFS, instead, and that’s the main reason I’m reluctant to update my iMac, as disk performance is markedly worse on hard drives with APFS.

Features I liked the most:

• I like that the screen can be locked with the keyboard shortcut ⌘-Ctrl‑Q.
• Intelligent Tracking Prevention in Safari 11: feature that uses machine learning to block third parties from tracking the user’s actions. Safari can also block autoplaying videos from playing. [W]

Features I was sad to see removed:

• FTP and telnet command line programs were removed in High Sierra.

Mac OS 10.14 Mojave

Released: 24 September 2018
Latest release (at the time of writing): 10.14.6 (Security Update 2021-002) — 9 February 2021
Wikipedia entry: here

As you may have guessed from the previous entry, I haven’t had the opportunity of using Mojave on any of my Macs, so I have little to say about it. It is generally considered a ‘good’ update, and many have praised the introduction of Dark Mode in its user interface. I’m not a fan of Dark Mode. I don’t think it is a great usability improvement, and I prefer using Light Mode and f.lux to reduce eye strain in the late hours of the day.

Features I liked the most:

• I certainly like the improved functionalities in the screenshot software and the new Screenshot app that replaces the venerable Grab app.
• I also like the new space in the Dock for recently used apps.

Worth mentioning:

Mac OS update functionality has been moved back to System Preferences from the Mac App Store. In OS X Mountain Lion (10.8), system and app updates moved to the App Store from Software Update. [W]

Mac OS 10.15 Catalina

Released: 7 October 2019
Latest release (at the time of writing): 10.15.7 Supplemental Update — 9 February 2021
Wikipedia entry: here

I used Catalina for less than two weeks before enrolling my 2015 13-inch retina MacBook Pro in the Big Sur beta programme, but based on the huge feedback I received about it (see my series of posts Mac OS Catalina: more trouble than it’s worth, starting from here), I consider 10.15 Catalina to be possibly the worst release in all history of Mac OS X.

Features I liked the most:

• Sidecar is perhaps the only new feature I really like in Catalina. Sidecar allows a Mac to use an iPad (running iPadOS) as a wireless external display. With Apple Pencil, the device can also be used as a graphics tablet for software running on the computer. [W]

Features I was sad to see removed:

• Dropping support for 32-bit apps is what I hate most about Catalina.
• I also disliked the split of iTunes into different apps (Music, Podcasts, TV, Books), all of lower quality than the sum of their parts that was iTunes.

Mac OS 11 Big Sur

Released: 12 November 2020
Latest release (at the time of writing): 11.2.3 — 8 March 2021
Wikipedia entry: here

Big Sur is the first Mac OS release in 20 years with a new numbering scheme — it’s not ‘Mac OS Ten’ anymore.

I’ve been beta testing Big Sur since August 2020, and I’ve been keeping a logbook on my blog, documenting my observations. You can start from the Intro if you’re interested.

Features I was sad to see removed:

• Network Utility has been deprecated.
• The ability to remove the menu bar clock.