Mac OS X
Mac OS X (officially pronounced "Mac OS Ten") is a line of
proprietary, graphical
operating systems developed, sold, and marketed by
Apple Computer, the latest of which is included with all currently shipping
Apple Macintosh computers. Mac OS X is the successor to the original
Mac OS, which had been Apple's primary operating system since 1984. Unlike its predecessor, Mac OS X is a
multi-user,
pre-emptively multitasking,
Unix-like operating system built on technology that had been developed at
NeXT through the second half of the 1980s and up until Apple Computer purchased the company in early 1997. The operating system was first released in 1999 as
Mac OS X Server 1.0, with a desktop-oriented version (
Mac OS X v10.0) following in March, 2001.
The server edition,
Mac OS X Server, is architecturally identical to its desktop counterpart but usually runs on Apple's line of Macintosh
server hardware. Mac OS X Server includes workgroup management and administration software tools that provide simplified access to key
network services, including a
mail server, a
Samba server, a
directory server, and a
domain name server.
Despite its branding as simply "version 10" of the
Mac OS, Mac OS X has a history that is almost completely independent of the earlier Mac OS releases.
Mac OS X is based on the
Mach kernel and the
BSD implementation of
Unix, which were incorporated into
NEXTSTEP, the
object-oriented operating system developed by
Steve Jobs's
NeXT company after he left Apple in
1985.
Meanwhile, during the years without Jobs at the helm, Apple attempted to create a "next-generation" operating system of its own (see
Taligent and
Copland) with little success.
Eventually, NeXT's OS—called
OPENSTEP at the time—was selected to form the basis for Apple's next OS, and Apple purchased NeXT outright
. Jobs was re-hired, and later returned to the leadership of the company, shepherding the transformation of the programmer-friendly OPENSTEP into a system that would be welcomed by Apple's primary market of home users and creative professionals, as a project known as
Rhapsody. After some missteps which threatened the loyalty of independent developers to Mac OS, and changes of strategy to ease the transition from Mac OS 9 to the new system, Rhapsody evolved into Mac OS X.
Mac OS X has evolved through its successive versions, away from a focus on
backward compatibility and toward "digital lifestyle" applications such as the
iLife suite, enhanced business applications (
iWork), and integrated home entertainment (the
Front Row media center).
|
The original (left) and revised (right) retail packaging for Mac OS X v10.4 "Tiger" |
Mac OS X was a radical departure from previous Macintosh operating systems as its underlying code base is completely different from previous versions. Its core, named
Darwin, is an
open source,
Unix-like operating system, built around the
XNU kernel with standard Unix facilities available from the
command line interface. On top of this core, Apple designed and developed a number of
proprietary closed source components, including the
Aqua user interface and the
Finder shell.
Mac OS X included a number of features intended to make the operating system more stable and reliable than Apple's previous operating systems.
Pre-emptive multitasking and
memory protection, for example, improved the ability of the operating system to run multiple applications simultaneously without their interrupting or corrupting each other. Many aspects of Mac OS X's architecture are derived from
OPENSTEP, which was designed with portability in mind, thus easing the transition from one platform to another. (For example, NEXTSTEP was ported from the original
68k-based NeXT workstations to
PA-RISC/
SPARC/
x86-based machines before NeXT was purchased by Apple, and OPENSTEP was subsequently ported to the
PowerPC architecture as part of Apple's
Rhapsody project.)
The most visible change was the
Aqua graphical user interface. The use of soft edges, translucent colors, and pinstripes (similar to the hardware of the first
iMacs), brought more color and texture to the windows and controls on the Desktop than OS 9's "Platinum" appearance had offered. Some, including numerous users of the older versions of the operating system, decried the new look as "cutesy"
[ Web-forum post by 'millennium'.] and lacking in professional polish. Others, however, hailed Aqua as being a bold and innovative step forward in a time when user interfaces were seen as being "dull and boring"
Mac OS X can run many
BSD or Linux software packages, as long as they have been compiled for the platform. Compiled binaries are normally distributed as Mac OS X packages, but some may require command-line configuration or compilation. Projects such as
Fink and
DarwinPorts provide precompiled or preformatted packages for many standard packages. Since version 10.3, Mac OS X has included
X11.app, the company's version of the
X11 graphical interface for Unix applications, as an optional component during installation. Apple's implementation is based on
XFree86 4.3 and X11R6.6, with a window manager which mimics the Mac OS X look, closer integration with Mac OS X, and extensions to use the native
Quartz rendering system and to accelerate
OpenGL. Earlier versions of Mac OS X can run X11 applications using
XDarwin.
For the early releases of Mac OS X, the standard hardware platform supported was the full line of Macintosh computers (laptop, desktop, or server) based on
PowerPC G3, G4, and G5 processors. Later versions of Mac OS X discontinued support for some older hardware; for example, Panther does not support "beige" G3s, and Tiger does not support systems that pre-date Apple's introduction of
FireWire ports. However, a patch can be applied to the installation disc, or free tools such as
XPostFacto have enabled installation of versions of Mac OS X on certain older systems not officially supported by Apple, including some pre-G3 systems. Except for features requiring specific hardware (e.g. graphics acceleration, DVD writing), the operating system offers the same functionality on all supported hardware.
Intel
In April
2002, eWeek reported a rumor that Apple had a version of Mac OS X running on x86 processors, code-named
Marklar. The idea behind Marklar was to keep Mac OS X running on an alternative platform should Apple become dissatisfied with the progress of the PowerPC platform.
These rumors subsided until late in May
2005, when
CNet reported that Apple would unveil Marklar in the coming months.
On
June 6,
2005, Steve Jobs confirmed these rumors when he announced in his keynote address at the annual Apple
Worldwide Developers Conference that Apple would be
making the transition from PowerPC to
Intel processors over the following two years, and that Mac OS X would support both platforms during the transition. The last time that Apple switched CPU families—from the
Motorola 68K CPU to the
IBM/Motorola PowerPC—Apple included a Motorola 68K emulator in the new OS that made almost all 68K software work automatically on the new hardware. Apple has supported the 68K emulator for 11 years; however, Apple will be dropping support for the 68K emulator during the transition to Intel CPUs. Included in the new OS for the Intel-based Macs is a new PowerPC emulator, named "Rosetta", that enables software compiled for PowerPC Mac OS X to run on Intel Mac OS X machines. However, Apple dropped support for
Classic mode on the new Intel Macs. (Third party emulation software, like
Mini vMac,
Basilisk II, and
SheepShaver, provides support for some early versions of Mac OS.) A new version of Xcode and the underlying command-line compilers support building Universal Binaries that will run on either architecture.
[ Apple's press release, announcing the transition to Intel.]Software developers can support the new Intel Macs in any of the following ways:#They can continue to ship PowerPC-only software, which will automatically work by using the Rosetta emulator which is included with the new OS that runs on Intel-based Macs.#They can ship Universal Binaries, which include both the PowerPC and x86 versions of their application. When the user opens the application, depending upon which CPU the Mac has, the appropriate version of the application will be run automatically.#They can ship x86-only Mac OS X applications that will run only on the new Intel-based Macs.
Currently, a lot of software is available only for PowerPC, and is supported with Rosetta. However, Apple encourages Developers to produce Universal Binaries with support for both PowerPC and x86. Universal Binary software should run faster on Intel-based Macs than PowerPC-only software running on Rosetta. Moreover, some PowerPC software, such as kernel extensions and System Preferences plugins, is not supported on Intel Macs. Option 3 will likely become the norm by about 2009 when the demand for PowerPC software drops off.
Support for the PowerPC platform will remain in version 10.5, although it is unclear how long this dual-architecture support will be continued—but because Apple supported the Motorola 68K family for eleven years after the introduction of PowerPC systems, it is likely that they will support the PowerPC Macs for many years to come. Jobs also confirmed rumors that Apple has had versions of Mac OS X running on Intel processors for most of its developmental life. Such crossplatform capability already existed in Mac OS X's lineage—the predecessor of Mac OS X, OPENSTEP, had been ported to many architectures, including Intel's x86, and a port to x86 of the core operating system of Mac OS X, Darwin, has been available as a free download since Mac OS X was first released. Also note that Apple stated that Mac OS would only run on Apple x86 systems, not PCs, but several people have been using a hacked version of the OS on non-Apple machines.
* Uses a subset of the
Portable Document Format (PDF) as the basis of its imaging model, named
Quartz.
* Full-color, continuously-scalable icons.
*
Drop shadows around window and isolated text elements to provide a sense of depth.
* Global application
services - spell checker, special characters palette, color picker, font chooser and dictionary.
*
Anti-aliasing of widgets, text, graphics and window elements.
* New interface elements including sheets (document modal
dialogs attached to specific windows) and drawers.
* Interweaving windows of different applications (not necessarily adjacent in the visible stacking order).
*
ColorSync color matching built into the core drawing engine (for
print and
multimedia professionals).
*
OpenGL composites windows onto the screen to allow hardware accelerated drawing. This technology (introduced in version 10.2) is called
Quartz Extreme.
*
Exposé (introduced in version 10.3) Instantly display all open windows as thumbnails for easy navigation to different tasks, display all open windows as thumbnails from the current application, and hide all windows to access the desktop.
* Pervasive use of
Unicode throughout the operating system.
* Straightforward architecture for
localization of applications and other code, fully separating language dependencies from the core code of a program.
*
FileVault (introduced in version 10.3) encrypts the user's Home folder with
Advanced Encryption Standard (AES) 128-bit keys.
*
Dashboard (introduced in version 10.4) supports small applications ("
widgets") that can be called up and dismissed in one keystroke.
*
Spotlight search technology (introduced in version 10.4) allows rapid real-time searches of data files, mail messages, photos, and other information, based on item properties (meta data) and/or content.
*
Automator (introduced in version 10.4) an application designed to create an automatic work-flow for different tasks.
*
Smart Folders (introduced in version 10.4) allow for dynamically updated folders depending on a set criteria.
* A well defined set of
Human Interface Guidelines followed by almost all applications giving them intuitive, consistent user interface and keyboard shortcuts.
*
Xgrid allows networked Macs to form a
distributed computing system.
* Built in virtual file system images
.dmg supporting encryption and compression, and optionally read/write capability.
* Integrated Sync Services (introduced in version 10.4) allows applications to access a centralized extensible database for various elements of user data, including calendar and contact items. The operating system manages conflicting edits and data consistency.
Mac OS X comes included in the price for new Macs. Minor upgrades are free and can be downloaded using
Software Update. Major upgrades cost US$129 (CAD$149) from Apple. There is also a US$199 (CAD$249) "Family Pack" version of Mac OS X that comes with 5 licenses for home users who have more than one Mac at home. Developers can register for free with the
Apple Developer Connection (ADC) to download developer tools such as
Xcode and documentation. ADC also offers several for-pay plans including both shipping and beta versions of Mac OS X. Student and educator pricing on Mac OS X software is roughly 10% to 50% lower than standard retail pricing. The Mac OS X Server 10-client license costs US$499 and an unlimited client license is US$999 as of
April 1,
2006.
The character
X is a
Roman numeral and is officially pronounced "ten", continuing the numbering of previous Macintosh operating systems such as
Mac OS 8 and
Mac OS 9. However, it is common to read it as the letter
X and pronounce it "ex". One possible reason for this interpretation is the tradition of giving
Unix-like operating systems names that contain the letter "X". (
AIX,
A/UX,
HP-UX,
IRIX,
Linux,
Minix,
Ultrix,
Xenix,
NeXT). Another possible reason is Apple's tendency to refer to specific versions in print (for example, "Mac OS X version 10.4").
Mac OS X versions are named after
big cats. Prior to its release, version 10.0 was
code named "
Cheetah" internally at Apple, and version 10.1 was code named internally as "
Puma". After the immense buzz surrounding Version 10.2, codenamed "
Jaguar", Apple's product marketing began openly using the code name to promote the operating system. 10.3 was similarly marketed as "
Panther". Version 10.4 is marketed as "
Tiger". "
Leopard" has been announced as the name for the next release of the operating system. Apple has also registered "
Lynx" and "
Cougar" as
trademarks.
Apple faced a lawsuit from a computer retailer named
Tiger Direct regarding its use of the name "Tiger". However, on
16 May 2005 the Florida Federal Court ruled that Apple's use of the name "Tiger" does not infringe upon Tiger Direct's trademark.
On a side note, Java version 5.0 (also known as version 1.5) from Sun Microsystems is named "Tiger" which may cause some confusion because it can be installed into Macs running Mac OS X.
Internally, Apple uses a "build number" to identify each development version of Mac OS X. There may be many development versions each week. Under Apple's guidelines, the first development version of a product starts with build 1A1. Minor revisions to that are 1A2, 1A3, 1A4, and so on; the first major development revision becomes 1B1 (and minor revisions to that would be 1B2, 1B3, etc.), the next major revision would be 1C1, and so forth. The next major revision after the last 1_ series would be 2A, followed by 2B. The transition from one letter to the next occurs with changes in the minor release number. For instance, the first build of Panther (10.3) was 7A1. The first public release was 7B85; the last, 10.3.9, was 7W98. But the next build of Mac OS X was 10.4, 8A1. When a build is chosen as the next public release of Mac OS X, it is given a public version number. Build 4K78 was chosen to be Mac OS X version 10.0, build 5G64 became 10.1, build 6C115 became 10.2, build 7B85 became 10.3, and build 8A428 became 10.4.
The current version of Mac OS X is 10.4.7 (released on
June 27,
2006). It is build 8J135 for PowerPC and 8J2135 for Intel.
10.4.4 was the first public version of Mac OS X to run on both PPC (build 8G32) and Intel-based Macs (8G1165). All previous versions of Mac OS X have Intel counterparts, but those were never publicized or made available to end-users.
Mac OS X v10.0 (Cheetah)
On
March 24,
2001, Apple released Mac OS X v10.0 (internally codenamed Cheetah). The initial version was slow, not feature complete, and had very few applications available at the time of its launch, mostly from independent developers. Many critics suggested that while the OS was not ready for mainstream adoption, they recognized the importance of its initial launch as a base on which to improve. Simply releasing Mac OS X was received by the Macintosh community as a great accomplishment, for attempts to completely overhaul the Mac OS had been underway since 1996, and delayed by countless setbacks. Following a few minor bug fixes, kernel panics became much less frequent, and Mac OS X began garnering praise for its stability at an early point in its development. It was criticized for being slow, with performance not much improved over the previous September's release of
Mac OS X Public Beta.
Mac OS X v10.1 (Puma)
Later that year on
September 25,
2001, Mac OS X v10.1 (internally codenamed Puma) was released, increasing the performance of the system as well as providing missing features, such as DVD playback. Apple released 10.1 as a free upgrade CD for 10.0 users, in addition to the US$129 boxed version for people running only
Mac OS 9. It was discovered that the upgrade CDs were actually full install CDs that could be used with
Mac OS 9 systems by removing a specific file; Apple subsequently re-released the CDs in an actual stripped-down format that didn't facilitate installation on such systems.
Mac OS X v10.2 (Jaguar)
On
August 24,
2002, Apple followed up with Mac OS X v10.2 "Jaguar" (the first release to use its code name as part of the branding) which brought profound performance enhancements, a newer, sleeker look, and many powerful enhancements (over 150, according to Apple), among them:
*Increased support for
Microsoft Windows networks
*
Quartz Extreme for compositing graphics directly on the AGP-based video card
*An adaptive
spam mail filter, based on
latent semantic indexing*A system-wide repository for contact information in the new
Address Book*
Rendezvous networking (Apple's implementation of
Zeroconf; renamed to Bonjour in 10.4)
*
iChat: an Apple-branded, officially-supported third party
AOL Instant Messenger client
*A revamped Finder with searching built directly into every window
*Dozens of new
Apple Universal Access features
*
Sherlock 3:
Web services (See
Watson)
*
CUPS: The Common Unix Printing System allowed the use of
Gimp-Print drivers, hpijs drivers, etc. for "unsupported" printers. It also allowed â€" with some user recompilation â€" printing to serial printers.
Mac OS X v10.2 was never officially referred to as Jaguar in the
United Kingdom due to an agreement with the automobile manufacturer
Jaguar, although boxes and CDs still bore the Jaguar-skin logo.
Some consider version 10.2, or Jaguar, the "first good release" of Mac OS X. Due to significant API changes, most developers don't support versions 10.0 or 10.1 any longer.
Also, the famous
Happy Mac that had served Mac users for almost 18 years during a Macintosh's startup sequence was replaced with a large grey Apple logo with the introduction of Mac OS X 10.2.
Mac OS X v10.3 (Panther)
Mac OS X v10.3 "Panther" was released on
October 24,
2003. In addition to providing much improved performance, it also incorporated the most extensive update yet to the user interface. The update included as many or more new features as Jaguar had the year before. On the other hand, support for some early G3 computers such as "beige" Power Macs and "WallStreet" PowerBooks was discontinued. New features of "Panther" include:
*Updated Finder, incorporating a brushed-metal interface, customizable sidebar and fast-searching
*
Exposé: a new system to manipulate and view windows
*
Fast User Switching: allows a user to remain logged in while another user logs in
*iChat AV which added
video-conferencing features to iChat
*Improved
PDF rendering to allow for faster PDF viewing
*Built-in
faxing support
*Much greater
Microsoft Windows interoperability
*
FileVault: on the fly encryption and decryption of a user's home folder
*Increased speed across the entire system with more support for the
G5*
Safari (web browser)Mac OS X v10.4 (Tiger)
Mac OS X v10.4 "Tiger" was released on
April 29,
2005. Apple stated that Tiger contains more than 200 new features. As with the release of Panther certain older machines have been dropped from the list of supported hardware; Tiger requires a Mac with built-in
FireWire ports. Among the new features of "Tiger":
*
Spotlight: A content- and
metadata-based file search tool, which finds items containing the key words you search for.
|
The Dashboard allows for miniature programs called "Widgets" to be superimposed over the desktop. When activated, the Dashboard "flies" onscreen as shown above. |
*
Dashboard:
Widgets for common tasks available on a desktop overlay accessible by a mouse gesture or keyboard function key, similar to Exposé. Its similarity with
Konfabulator caused some criticism.
*
Smart Folders: A virtual folder that uses
Spotlight to populate the file listing instead of showing a true folder on the filesystem.
*Updated Mail program with Smart Mailboxes, allowing virtual mailboxes defined by
Spotlight searches.
*A new version of
iChat: A new version supports the
H.264/MPEG-4 AVC video codec for conferencing and allows for multi-party audio and video chats. Support for the
Jabber online
instant messaging protocol is also introduced. (Mac OS X version 10.4.3 and later also include support for encrypted chat via
.Mac.)
*A new version of
QuickTime 7: the new version includes
H.264 support and a completely re-written interface.
*A new version of
Safari 2: this new version of the system's default web browser includes the ability to view RSS feeds directly in the browser, among other new features.
*
Automator: automates repetitive tasks without programming.
*
VoiceOver: A built-in screen reader for those with vision disabilities.
*
Core Image and
Core Video: allows additional effects in video and image editing to be performed in real time.
*
64-bit memory support for the new
G5 for programs or program parts without a graphical user interface, with an
LP64 programming model (graphical user interface front ends still must be programmed in 32-bit).
*Updated Unix utilities, such as
cp,
mv and
rsync, now respect
HFS Plus metadata and
resource forks. (cp in 10.4 is like CpMac, mv is now like MvMac, compatibility issues naturally arise.)
*An extended permissions system using
access control lists.
*A brand-new
Application Programming Interface called
Core Data, which greatly faciliates creating database-driven
Cocoa applications.
* Added Sync Services, an operating system managed truth database exposed to applications via a published
Application programming interface. Applications use Sync Services as a conduit to other applications, or the the users other computers or mobile devices. This service is featured in the operating system with the
Address Book,
iCal, and
Mail applications as well as the
Apple Keychain using this service.
An
Intel x86 version of Mac OS X Tiger was previewed by Apple, and subsequently leaked to the Internet, following Apple's announcement to switch to the Intel platform. It was revealed by Apple at the June 2005
Worldwide Developers Conference that Intel versions of all previous versions of Mac OS X had been compiled internally, keeping feature parity between the Intel and
PowerPC versions, "just in case." Developers were provided the chance to buy an Intel-based Pentium 4 developer transition system loaded with 10.4.1 in June 2005, and 10.4.2 and 10.4.3 were released to developers in September and November 2005 respectively. 10.4.4 was the first update to Mac OS X that was released through
Software Update. All new
Intel Macs are preloaded with Intel versions of Mac OS X Tiger.
Soon after the release of the developer transition kits, copies of the Intel version of Mac OS X were released onto the Internet and a community effort called
OSx86 started up to help coordinate efforts to get Mac OS X running on non-Apple hardware. As each update was released, patches were updated to circumvent Apple's efforts to lock their operating system to their hardware.
Mac OS X v10.5 (Leopard)
|
Leopard promotional disc art shown at WWDC 2006 |
Mac OS X v10.5 "Leopard" was announced at the
Worldwide Developers Conference on
June 6 2005, and was shown to developers for the first time at the 2006 Worldwide Developers Conference on
August 7 2006. Steve Jobs stated that OS X Leopard will be available in "Spring 2007". Apple has said it will support both
PowerPC- and
Intel x86-based Macintosh computers. Though Apple maintains that "All features referenced in the Mac OS X Leopard Sneak Peek are subject to change,"
[http://www.apple.com/macosx/leopard/] some officially previewed features include:
*
Time Machine - It allows the user to go back and restore any file that's been lost or deleted, or can revert to an older version of a file.
*Spaces - It allows the user to create multiple "
virtual desktops" or "spaces" and switch between them, allowing the user to organize each space by purpose (work, entertainment, etc).
*Full support for 64-bit applications, including graphical applications.
Early reports show Apple drawing heavy ironic comparison with Microsoft's Windows Vista, using banners announcing "Introducing Vista 2.0" and "Hasta la vista, Vista".
On
April 5 2006 Apple released an application called
Boot Camp, which helps users of Intel-based Macs to
dual boot between Mac OS X and
Microsoft Windows XP. Apple simultaneously published a firmware update with
BIOS support (as Windows does not support the
Extensible Firmware Interface (EFI) used in all Intel Macs), and the Boot Camp software automatically repartitions the user's hard disk to a custom size, and burns Windows drivers to a CD. Boot Camp is currently in public beta, with the final version intended to be included in Leopard.
*
Architecture of Mac OS X*
Comparison of BSD operating systems*
Comparison of operating systems*
FreeBSD â€" the FreeBSD operating system is the reference platform for Apple's UNIX implementation.
*
History of Mac OS X*
NetBSD â€" parts of Apple's UNIX implementation were sourced from the NetBSD operating system.
*
OpenBSD â€" parts of Apple's UNIX implementation were sourced from the OpenBSD operating system.
*
List of Mac OS X technologies*
List of Macintosh software*
PearPC â€"
PowerPC emulator capable of running Mac OS X
*
ipfirewall â€" the official
firewall of Mac OS X
*
Apple: Mac OS X — The official page for Mac OS X.
*
What is Mac OS X? (kernelthread.com) — An overview of the Mac OS X operating system
*
Mac OS X (arstechnica.com) — Comprehensive reviews of Mac OS X (all versions)
*
Mac OS X: Welcome to the jungle — A look inside the Mac OS X software ecology (Free Software Magazine, March 2005)
*
MacOSXHints — a website of Mac OS X hints going back to the public beta.
*
Mac OS X vs. Windows XP*
Info on Mac OS X from OSdata (last updated March 4, 2002)
*
Info on Mac OS X Server from OSdata (last updated February 14, 2002)