The OSX/MacOS or operating system regulates the way in which Mac computers run and often provides new functionality to the device.  Sometimes, a new version of the operating system may simply be an overhaul of the appearance of the operating system whereas other updates may result in significant features.  Note that, unlike iPads, while updates may be applied freely to almost all devices, upgrading may have detrimental benefits to the computer particularly if the computer's hardware capabilities are not powerful enough to support the software demands.  Below, is a list of changes that each major OSX/MacOS version brought with it (starting with OSX 10.).

OSX/MacOS Timeline

OSX 10.0 Cheetah (2001)

This is the one that kicked it off and was the successor to OS 9 (the last of the numerical progression, after which future versions became derivatives of OSX 10).  The first releases followed a nomenclature that were related to big cats.

OSX 10.1 Puma (2001)

The successor to the initial release provided performance upgrades and DVD playback.  Unlike the modern releases, Apple charged its users to upgrade until OSX 10.9 was released.

OSX 10.2 Jaguar (2002)

This version was probably the first major overhaul to the Apple ecosystem featuring not only performance upgrades but user-interface enhancements.  This is also the first introduction to the use of the Apple logo as opposed to the "Happy Mac" symbol that had been used for the previous 18 years.

OSX 10.3 Panther (2003)

Following on the success of its predecessor, Panther saw more of the continued rollouts in terms of performance and interface additions.  This version introduced Expose giving the operating system a functional windows management system.  It is also the first version to feature Safari, Apple's proprietary browser.

OSX 10.4 Tiger (2005)

At around this time, the operating system was starting to outpace the capabilities of older hardware an certain models were no longer supported.  Classic features that were introduced and whch continue to exist on modern versions of the operating system include Spotlight (internal search engine), Dashboard (widget panel), Smart Folders, QuickTime, Automator, and Voiceover (accessibility feature for visually impaired users).

OSX 10.5 Leopard (2007)

New features introduced in this version include an updated Finder, Time Machine (for backing up and restoring files), Spaces (advanced windows management in conjunction with Expose, Boot Camp (allowing dual operating system functionality), and improved Mail features.

OSX 10.6 Snow Leopard (2009)

For the past few years, each successive operating system release has featured functionality enhancements.  Snow Leopard focused instead on performance, stability and efficiency measures.  One major addition however was the introduction of the Mac App Store to distribute software digitally.

OSX 10.7 Lion (2011)

This release brought some harmony between the user experience on an iPad to the Mac such as the use of gestures on the trackpad and Launchpad.

OSX 10.8 Mountain Lion (2012)

This release moved the trend of having upgrades every two years to an annual cycle.  It provided further harmonization between the mobile ecosystem to the Mac ecosystem such as support for Messages, Calendar, iCloud, and Notification Center.

OSX 10.9 Mavericks (2013)

One of the greatest significance of this release was that it was provided free to previous Snow Leopard users, a standard that would apply to future updates.  This version added the Maps and iBooks applications which had only been available previously on iOS devices.  Note that the naming convention also shifted to California landmarks.

OSX 10.10 Yosemite (2014)

The path of further harmonizing both platforms continued with this version which sought to mimic the look of iOS7.  The greatest new feature was handoff, the first of many Continuity features.  Also, Apple retired iPhoto and Aperture replacing it instead with Photos.

OSX 10.11 El Capitan (2015)

Not a whole lot of new features but continued stability and a "cleaner" look.

MacOS 10.12 (2016)

Apple abandoned the OSX moniker and renamed its operating system MacOS instead but kept the numbering system.  This version saw the porting of Siri, previously developed for its mobile devices.  Sadly, unlike the mobile devices, Siri is not able to be activated natively without a key touch.

MacOS 10.13 High Sierra (2017)

Although most users might not notice a difference, Apple switched over its disk writing system to a new format called APFS (Apple File System).

MacOS 10.14 Mojave (2018)

This is Apple's first foray into introducing iOS apps to the MacOS environment.  The initial move will only see a few apps supported (Home, News, Voice Memos, Stocks) with the expectation that more apps will be added in the future.

Apple has announced that this will be the last MacOS that will support 32 bit apps.  This version of MacOS will drop support for many older Mac versions as it requires the use of Metal to operate.  

MacOS 10.15 Catalina (2019)

The greatest change during its inaugural announcement in June was that iTunes would be replaced with three separate apps: Apple Music, Apple Podcasts and Apple TV.  This version will also build upon the previous MacOS vision of integrating iPad apps.  Another new feature announced is Sidecar which will allow an iPad to be used as a second screen and as a drawing tablet, something that was only previously achievable through the use of third party applications.  In terms of accessibility, MacOS will feature a new tool called Voice Control that will allow a user to control their computer with their voice.  A significant impact that this update will bring to existing users is that 32bit programs will no longer run on Catalina.

MacOS 11 Big Sur (2020)

This is the first time in almost two decades that Apple has changed its numerical formatting for labelling it's operating system.  It departs from the traditional use of OS 10.x and is the first use of version 11.  It will be interesting to see if the next version moves to 12 or continues to use the 11 format.  Apple continues to improve and highlight its privacy tools with additional tools embedded in this release.  This includes password monitoring within Safari resulting in an alert in the event of a data breach.  Safari will also offer a weekly privacy report that summarizes your browsing history and what actions were taken to ensure privacy.  This is Apple's attempt at recovering browser share over Chrome and they have claimed that Safari can now load websites 50% faster at an improved power efficiency.  Other enhancements to Safari include an improved tab design, translation into 7 languages, and Safari extensions.  Apple has mimicked the Control Center feature that users may be familiar with on their phones and iPads and incorporated it into the MacOS platform.  Like its counterparts, the Control Center is customizable.  They have also cleaned up and simplified the notification center which is also where widgets are now located. 

MacOS 12 Monterey (2021)

Released in the Fall of 2021 as the traditional date of previous releases.  Currently, Apple has revealed the following features that will be incorporated in this new update:

• Introduction of Shortcuts, previously only available on the iPad.  Allows for customized macros to execute complex tasks.

• Universal control of accessories such as keyboards and a mouse to be used across Apple products (Macs and iPads).

• Major upgrade to FaceTime application which incorporates the SharePlay feature allowing multiple users to access the same multimedia content simultaneously

• Live Text recognition within Photos, Screenshot, Quick Look and Safari (M1 devices only)

• Focus controls to regulate notifications on devices

• Upgraded AirPlay that allows streaming both audio and visual content to the Mac from other Apple devices

MacOS 13 Ventura (2022)

Released in the Fall of 2022 as the traditional date of previous releases.  One major change is the level of support for older devices has been removed.  The baseline requirement is now 2017 (iMac, iMac Pro, MacBook Pro, MacBook) and 2018 (MacBook Air, Mac mini), 2019 (Mac Pro) devices or newer.  The following features will be incorporated in this new update:

• improved Mail features including better search functionality, undo or schedule emails, and rich links.

• Better searching capabilities in Spotlight particularly for images.  Integration with common actions within the Spotlight results.

• improvements to Safari including introduction of Passkeys touted to be a more secure login.  Sharing of tabs and bookmarks, sending messages and starting FaceTime conversations within Safari.

• Editing sent Messages or sharing media within Messages.  Greater collaboration.

• Sharing of photos and videos with up to five people and greater sharing controls.

• Stage Manager is a new organizational tool that groups apps and windows in a single view allowing more efficient workspace management.

• Seamlessly transition to use of iPhone camera for projects and communications

• New Freeform app

• Accessibility improvements: live captioning, better dictation

MacOS 14 Sonoma (2023)

Released in the Fall of 2023 as the traditional date of previous releases.  It officially ends support for Macs without retina display and all models of 12-inch MacBook.  New features include:

• the reintroduction of Print Center, first introduced in 2005, allowing for management of print jobs

• addition of widgets to the desktop to execute common tasks

• access widgets on iPhone from Mac computer through Continuity

• easier way to screen share from a video call

• enhanced AutoFill on PDF documents using information from contacts

• more accurate autocorrect; tap space bar to complete words or sentences

• Personal Voice helps users with speech loss create a voice that sounds like them

• new experience for learning how to use Voice Control

• use Dictation and the keyboard together to move fluidly between the two

MacOS 15 Sequoia (2024)

This latest version of Apple's operating system focuses heavily on Apple's artificial intelligence engine named Apple Intelligence.  While the operating system update is available for multiple devices, Apple has indicated that Apple Intelligence features are designed to work with Mac models that contain the Silicon chip.   It officially ends support for MacBook Airs released prior to 2020.  New features include:

• new writing tools and language capabilities to assist with writing, summarizing

• improved Siri functionality

• greater continuity functionality with an iPhone including receiving notifications on a Mac from an iPhone, drag and drop between devices

• better window management

• a redesigned Reader in the Safari browser which provides a table of contents and a summary of an article

• live audio transcription

• calculating, evaluating expressions and assigning variables for math within the Notes application

MacOS 25 Tahoe (2025)

You may be wondering where the previous versions between 15 (Sequoia) and 24 disappeared to.  Apple has revised their numbering system such that the version number will align with the date in which it was released.  This numbering system will equally apply to other Apple operating systems such as iOS, iPadOS, etc. 

Of specific significance to this latest release, Apple has introduced a new user interface design which they have coined Liquid Glass and will be harmonized across all of their platforms.  This version of macOS will be the last version that will be supported on the older Intel-based Macs (available only on limited models).  It will also be the first instance in which the operating system will not be upgradeable from the Mac App Store and must be installed via the System Settings software panel.

As part of its overall interface overhaul, the design will be reflected in many aspects of the user experience including the appearance of folders (highly customizable), icons, menu bar, control center (more closely resembling iOS version), sliders, and Lock Screen customization features.  Broadly speaking, users can expect their experience to be more uniformly harmonized across Apple devices particularly if one is accustomed to using an iPhone or an iPad.

As is the general trend, there is a gradual shift towards AI integration which for Apple specifically refers to Apple Intelligence.  This is embodied by Spotlight search functionality enhancements.