Encyclopedia
Mac OS X is a line of proprietary, graphical
operating systems developed, marketed, and sold by
Apple Computer, the latest of which is pre-loaded on all currently shipping
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 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.
History
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 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 , and integrated home entertainment .
Description
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 themed
Quartz Compositor 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.
The most visible change was the Aqua theme. The use of soft edges, translucent colors, and pinstripes , 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" 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". Despite the controversy, the look was instantly recognizable, and even before the first version of Mac OS X was released, third-party developers started producing
skins for customizable applications, like
Winamp, similar to the Aqua appearance.
Mac OS X includes its own
software development tools, most prominently an integrated development environment called
Xcode. Xcode provides interfaces to compilers that support several programming languages including
C,
C++, Objective-C, and
Java. It supports the ability to target both platforms for which Mac OS X is sold, allowing an application to be built to run only on PowerPC, only on x86, or on both processors as a
Universal Binary.
Compatibility
PowerPC
PowerPC versions of Mac OS X retain compatibility with older
Mac OS applications by providing an emulation environment called Classic, which allows users to run
Mac OS 9 as a process within Mac OS X, so that most older applications run as they would under the older operating system. In addition, the
Carbon APIs for Mac OS 9 and Mac OS X were created to permit code to be written to run natively on both systems. The OpenStep APIs are still available, but Apple now calls the technology
Cocoa. A fourth option for developers is to write applications in the Java platform, which Mac OS X has supported as a "first class citizen"—in practice this means that Java applications fit as neatly into the operating system as possible while still being "cross-platform", and that
GUIs, although being written in Swing, look almost exactly like native Cocoa interfaces. Traditionally, Cocoa programs have been mostly written in Objective-C, with Java as an alternative. However, on July 11, 2005, Apple announced that "features added to Cocoa in Mac OS X versions later than 10.4 will not be added to the Cocoa-Java programming interface."
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 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 , 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 various media outlets, such as the
Wall Street Journal and
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
Rosetta, a translator layer 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. A new version of Xcode and the underlying command-line compilers support building Universal Binaries that will run on either architecture.
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 Rosetta, 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. Although Apple stated that Mac OS X would not run on Intel-based personal computers aside from its own, a hacked version of the OS developed by the OSx86 community is available illegally through file-sharing networks. However it is no longer up to date with Apple's system updates; using the kernel from a previous update.
Prominent features
- Uses a subset of the Portable Document Format 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 and drawers.
- Interweaving windows of different applications .
- ColorSync color matching built into the core drawing engine .
- OpenGL composites windows onto the screen to allow hardware accelerated drawing. This technology is called Quartz Extreme.
- Exposé 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 encrypts the user's Home folder with Advanced Encryption Standard 128-bit keys.
- Dashboard supports small applications that can be called up and dismissed in one keystroke.
- Spotlight search technology allows rapid real-time searches of data files, mail messages, photos, and other information, based on item properties and/or content.
- Automator an application designed to create an automatic work-flow for different tasks.
- Smart Folders 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 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.
Pricing
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 from Apple. There is also a US$199 "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 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.
Naming
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". . Another possible reason is Apple's tendency to refer to specific versions in print .
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, version 10.5. 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.
Java 5.0 from
Sun Microsystems is also code-named "Tiger".
Versions
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 , 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 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 . 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 and Intel-based Macs . 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
On March 24, 2001, Apple released Mac OS X v10.0 . 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
Later that year on September 25, 2001, Mac OS X v10.1 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
On August 24, 2002, Apple followed up with Mac OS X v10.2 "Jaguar" which brought profound performance enhancements, a newer, sleeker look, and many powerful enhancements , 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
- 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 service
The W3C [i] defines a
Web service as a software system designed to support interoperable [i]...
s
- CUPS: The Common Unix Printing System allowed the use of Gimp-Print drivers, hpijs drivers, etc. for "unsupported" printers. It also allowed — with some user recompilation — 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
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
Mac OS X v10.4
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.
- 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.
- 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 .
- Updated Unix utilities, such as cp, mv and rsync, now respect HFS Plus metadata and resource forks.
- An extended permissions system using access control lists.
- A brand-new Application Programming Interface called Core Data, which greatly faciliates the management of application data in 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
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," some officially previewed features include:
- Time Machine: An automated backup utility which allows the user to restore any file that has been deleted, misplaced or replaced by another version of a file.
- Spaces: an implementation of "virtual desktops" for Mac OS X, allowing users to have multiple desktops per computer and be able to place certain applications and windows in a desktop. Users can organize certain Spaces for certain applications and switch between them. Exposé will work inside Spaces, allowing the user to see all at a glance all desktops fitted onto one screen.
- Full support for 64-bit applications, including graphical applications.
- New features in Mail, such as templates, notes, to-dos, and an RSS reader.
Publicity materials at WWDC 06 made dismissive comments towards Microsoft's
Windows Vista, using banners which read, "Introducing Vista 2.0" and "
Hasta la vista, Vista".
On April 5 2006 Apple released an application called Boot Camp, which allows Intel Macs to dual boot between Mac OS X and
Microsoft Windows XP. Apple simultaneously published a firmware update with
BIOS support , 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.
Criticisms
While OS X has a very strong fan base among its users, some advanced users are critical of some features of the operating system. In February 2001, the Dock was criticised by Bruce Tognazzini for being more about improving the Mac's "curb appeal" and demoability than being a useful tool. He further pointed out a list of problems with the Dock including that, although it can be resized, in its default states it takes up four times more space in pixels than the
Windows Task bar and the Mac
menu bar. Also that the Dock floats above all applications, so the user often has to either hide the Dock or avoid windows from overlapping it.
See also
|-
| colspan="2" style="text-align:center;" | br/>br />FreeBSD welcome screen
...
— the FreeBSD operating system is the reference platform for Apple's UNIX implementation.
...
— parts of Apple's UNIX implementation were sourced from the OpenBSD operating system.
- List of Mac OS X technologies
- List of Macintosh software
- PearPC — PowerPC emulator capable of running Mac OS X
- ipfirewall — the official firewall of Mac OS X
References
External links
- — The official page for Mac OS X.
- — An overview of the Mac OS X operating system
- — Comprehensive reviews of Mac OS X
