macOS Sierra (version 10.12) is the thirteenth major release of macOS
(formerly known as OS X and Mac OS X), Apple Inc.'s desktop and server
operating system for Macintosh computers. The name "macOS" stems from the
intention to unify the operating system's name with that of iOS, watchOS
and tvOS. Sierra is named after the Sierra Nevada mountain range in
California and Nevada. Specifically, Lone Pine Peak is the location for
macOS Sierra's default wallpaper. Its major new features concern
Continuity, iCloud, and windowing, as well as support for Apple Pay and
Siri.
Developed by: Apple Computer, Inc.
General availability: September 20, 2016 (version 10.12 build 16A323 -
original Mac App Store release)
Last release: September 26, 2019 (version 10.12.6 build 16G2136 - final
security update; scroll down and click on "Release History" for all
builds)
Preceded by: OS X El Capitan (version 10.11)
Succeeded by: macOS High Sierra (version 10.13)
Kernel type: Hybrid (XNU)
Support status: Obsolete, unsupported as of September 2019. iTunes is no
longer being updated, but is able to download driver updates to sync to
newer devices.
The first beta of macOS Sierra was released to developers shortly
following the 2016 WWDC keynote on June 13, 2016. The first public-beta
release followed on July 7, 2016. It was released to end users on
September 20, 2016, as a free upgrade through the Mac App Store and it was
succeeded by macOS High Sierra on September 25, 2017.
Systen Requirements
macOS Sierra requires at least 2 GB of RAM and 8 GB of storage space and
is designed to run on the following products:
- iMac (Late 2009 or later)
- MacBook (Late 2009 or later)
- >MacBook Air (Late 2010 or later)
- MacBook Pro (Mid 2010 or later)
- Mac Mini (Mid 2010 or later)
- >Mac Pro (Mid 2010 or later)
Sierra dropped support for various Macs released from mid 2007 to mid
2009, the first version of macOS since OS X Mountain Lion, released in
2012, to do so. Support for Xserve was also dropped in Sierra.
Workarounds for unsupported systems
Some developers have created workarounds to install macOS Sierra on
certain Mac computers that are no longer officially supported as long as
they are packed with a CPU that supports SSE4.1. This requires using a
patch to modify the install image.
Features
System features
Siri
The user can access the Siri intelligent assistant via the Dock, the
menu bar or a keyboard shortcut and results are shown in a window in
the upper-right corner. Siri can send messages, search the web, find
files and adjust settings. Results can be dropped into other
applications or pinned to Notification Center. For instance, pictures
from search results can be dragged into a document.
iCloud Drive and Optimized Storage
iCloud Drive can upload the user's documents and desktop directories
and sync them to other devices. The System Information application has
a new section that gives the user detailed information about space
usage per application or file and provides tools and suggestions for
freeing up space. For instance, the user can let the system upload old
files to iCloud Drive and remove their local copies, keeping them
available on-demand in Finder. It can also remove old files from trash
automatically. iTunes can delete watched, purchased films and TV
programs from its library.
Auto Unlock and Universal Clipboard
Building upon Continuity, an "umbrella term [for] features that
facilitate the communication between [Apple devices]" using Bluetooth
and Wi-Fi, Sierra adds two features. With Auto Unlock, the user can
unlock their user account by holding a paired Apple Watch close to the
device. Time of flight is used to prevent relay attacks. Auto Unlock
requires a Mac that was introduced in 2013 or later. With Universal
Clipboard, the user can share the clipboard for cut, copy and paste
between macOS Sierra and iOS 10 devices, including text and rich
content, such as pictures or videos.
Tabs and Picture-in-Picture
Applications that support multiple windows can support multiple tabs
within a single window, allowing the user to keep windows organized
similarly to Safari. With Picture-in-Picture, videos can be played in
a window that follows the user across the system.
Apple File System
Apple released a preview of a new file system in Sierra, called Apple
File System (APFS), to overcome the limitations of HFS Plus. APFS is
intended for solid-state drives and flash memory and adopts several
features found in modern file systems, such as snapshots and cloning,
as well as native support for features that Apple already provides in
HFS Plus through supplementary software, such as file-system
encryption and TRIM support. The file system was released in macOS
High Sierra.
Night Shift
Night Shift is new in macOS 10.12.4, with the same functionality as
its iOS counterpart. Night Shift reduces blue light at night to aid
sleep. This can be scheduled in the System Preferences app (in the
Displays menu) and can be toggled on or off in the Notification Center
or using Siri.
Since this feature relies on the Metal framework, Night Shift is not
available on all systems that support macOS Sierra.
Application features
Photos
Apple says it has improved the face recognition of the Photos
application, adding object and scene recognition. It groups similar
pictures together using faces, locations and object recognition to
create "memories". Memories contain picture slideshows with
transitions and music selected by the algorithm, which can be modified
to the user's liking. The "People" album organizes photos by the
people in them, and Places shows all photos on a world map.
Safari and Apple Pay
Safari provides an "extension point" which enables developers to
bundle Safari extensions within their Cocoa applications and
communicate with them directly from the applications. Safari conceals
the presence of installed "legacy" plug-ins, such as Adobe Flash
Player, Java applets, Microsoft Silverlight, and QuickTime - from
websites and requires the user to enable a specific plug-in on a
per-use or per-website basis.
Apple Pay allows vendors to embed an Apple Pay button on their
websites. In Safari, users can click the Apple Pay button to check
out, then complete a purchase using an iPhone or Apple Watch. Apple
Pay requires a Mac that supports Continuity (2012 or later models) and
either an iPhone 6 or later with iOS 10, or an Apple Watch with
watchOS 3.
Messages
The Messages app adds aesthetic effects to messages, such as three
times bigger emojis and click back with hearts or thumbs-up on a
message bubble. The ability to play YouTube videos and preview links
in a conversation was introduced. Users can view interactive content
added to iMessage in iOS 10. The app also allows you to turn on or off
read receipts on a conversation by conversation basis.
iTunes
Apple Music within iTunes has been redesigned, making it simpler to
find favorite songs and discover new ones. A new "For You" tab has
been added, which suggests new music the user might like (similar to
the existing Genius). A refined MiniPlayer with the ability to view
lyrics while listening has also been introduced.
Notes
The Notes app allows the user to share and collaborate on notes. This
is done by clicking on a share button at the top of the window.
Other changes
-
Disk Utility regains the ability to format and manage RAID sets,
after it was removed in El Capitan.
-
Finder has an option to show folders always at the top of the view
hierarchy, for instance in list views.
-
Mail adds a control to the top of email lists to quickly filter
them, for instance, by read status or the presence of attachments.
-
13 & 15-inch Retina MacBook Pros now default to integer scaled over
nearest-neighbor scaled resolutions to fit more content.
Security improvements
Gatekeeper
macOS Sierra slightly changes the Gatekeeper user interface and adds
two new mechanisms. A new default in System Preferences hides the
"Anywhere" option which allows the user to disable the mechanism and
execute programs from any source without needing to approve each new
one individually.
The first new mechanism allows developers to code-sign disk images
that can be verified as a unit by the system. This allows developers
to guarantee the integrity of external files that are distributed
alongside the application bundle on the same disk image. An attacker
could infect these external files with malicious code and with them
exploit a vulnerability in the application, without having to break
the signature of the application bundle itself. By signing the disk
image, the developer can prevent tampering and force an attacker to
repackage the files onto a new disk image, requiring a valid developer
certificate to pass Gatekeeper without a warning.
The second new mechanism is "path randomization", which executes
application bundles from a random, hidden path and prevents them from
accessing external files relative to their location. To avoid this,
the developer has to distribute the application bundle and its
external files on a signed disk image or in a signed installer
package. The user can avoid this mechanism by moving the application
bundle without its external files to a new location.
Directory permissions and sudo
The Unix permissions for writing to the
/Volumes directory are now restricted to root and no
longer "world-writable". Apple expanded System Integrity Protection to
/Library/Application Support/com.apple.TCC, a directory
that contains a list of applications that are allowed to "control the
computer", and restricts write access to programs which were signed
with an Apple "private entitlement". The file-hosting service Dropbox
has been criticized for manipulating the directory to add their
Dropbox application to the list, rather than asking the user to do it
for them explicitly in System Preferences.
The sudo command-line utility with which a user can execute a command
as another user, typically as root, is configured with the
"tty_tickets" flag by default, restricting the session timeout to the
terminal session (such as a window or tab) in which the user
authenticated the program.
Removed functionality
-
Sierra removes support for garbage collection from the Objective-C
runtime, a memory-management system that was added in Mac OS X Leopard
(version 10.5) and declared deprecated in favor of Automatic Reference
Counting in OS X Mountain Lion (version 10.8). Applications that have
been compiled with garbage collection will no longer run.
-
Apple removed native support for the VPN protocol PPTP and made
recommendations for alternatives that it considers more secure.
-
The battery's "time remaining" estimate was removed in the 10.12.2
update after complaints of the battery life of 2016 MacBook Pros.
-
The Game Center app has been removed. However, the service still
exists.
