Mac OS X

File:OSXLeopard.png
A screenshot of the desktop and Finder in Mac OS X 10.5 "Leopard"
Developer	Apple Inc.
OS family	Unix
Working state	Current
Source model	Closed source (with open source components)
Latest release	10.5.1 / November 15 2007
Platforms	x86, x86-64, PowerPC (32-bit & 64-bit), ARM
Kernel type	Hybrid kernel
Default user interface	Aqua (GUI)
License	Proprietary EULA
Official website	Apple - Mac OS X

Mac OS X (Template:PronEng) is a line of graphical operating systems developed, marketed, and sold by Apple Inc., 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 predecessors, Mac OS X is a Unix-based operating system^[1] built on technology that had been developed at NeXT through the second half of the 1980s until Apple purchased the company in early 1997.

The first version released was Mac OS X Server 1.0 in 1999, and a desktop-oriented version, Mac OS X v10.0 followed in March 2001. Since then, five more distinct "end-user" and "server" versions have been released, most recently Mac OS X v10.5 in October 2007. Releases of Mac OS X are named after big cats, for example Mac OS X v10.5 is usually referred to by Apple and users as "Leopard".

The server edition, Mac OS X Server, is architecturally very similar to its desktop counterpart but usually runs on Apple's line of Macintosh server hardware. It includes workgroup management and administration software tools that provide simplified access to key network services, including a mail transfer agent, a Samba server, an LDAP server, a domain name server, and others.

Apple also produces customized versions of OS X for use on three of its consumer devices, the Apple TV^[2], the iPhone and the iPod touch. The modified OS only contains what is needed for that particular device (un-needed drivers and components are removed), though certain sources have reported that simple hacks could install features in the Mac OS to the stripped down version, which could indicate Apple wants to improve upon a common platform on all its hardware devices.^[3]

History

Mac OS X is based on the Mach kernel and is derived from the Berkeley Software Distribution (BSD) implementation of Unix in Nextstep. Nextstep was the object-oriented operating system developed by Steve Jobs' company "NeXT" after he left Apple in 1985.^[4] While Jobs was away from Apple, Apple tried to create a "next-generation" OS through the Taligent and Copland projects, with little success.

Eventually, NeXT's OS — then called OPENSTEP — was selected to be the basis for Apple's next OS, and Apple purchased NeXT outright.^[5] Steve Jobs returned to Apple as interim CEO, and later became CEO again, 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. The project was first known as Rhapsody, and was later renamed to Mac OS X.^[6]

With each new version, Mac OS X evolved away from a focus on backward compatibility with the earlier versions of Mac OS, toward an emphasis on "digital lifestyle" applications such as the iLife suite, enhanced business applications (iWork), and integrated home entertainment (the Front Row media center). Each version also included modifications to the general interface, such as the brushed metal appearance added in version 10.2, the "unified" titlebar appearance in version 10.4, and slight changes in the appearance of the "streetlight" buttons.

Description

Mac OS X was a radical departure from previous Macintosh operating systems; its underlying code base is completely different from previous versions. Its core, named Darwin, is a free and open source Unix-like operating system (OS) built on top of the XNU kernel, with standard Unix facilities available from the command line interface. Apple layered over Darwin a number of components, including the Aqua interface and the Finder, to complete the GUI-based operating system which is Mac OS X.

Mac OS X included a number of features intended to make the OS more stable and reliable than Apple's previous OSs. For example, pre-emptive multitasking and memory protection improved the system's ability to run multiple applications simultaneously without them interrupting or corrupting each other.^[7] Many aspects of Mac OS X's architecture are derived from Openstep, which was designed to be portable — to ease the transition from one platform to another. For example, Nextstep was ported from the original 68k-based NeXT workstations to other architectures before NeXT was purchased by Apple, and Openstep was later ported to the PowerPC architecture as part of the Rhapsody project.

The most visible change was the Aqua theme. The use of soft edges, translucent colors, and pinstripes — similar to the hardware design of the first iMacs — brought more texture and color to the user interface than OS 9's "Platinum" appearance had offered. Many users of the older versions of the operating system decried the new look as "cutesy" and lacking professional polish.^[8] But, others found Aqua to be a bold and innovative step forward in a time when user interfaces were seen as "dull and boring".^[9] 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 which mimicked the Aqua appearance. To some extent, Apple has used the successful transition to this new design as leverage, at various times threatening legal action against people who make or distribute software with an interface the company claims is derived from its copyrighted design.^[10]

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. For the Apple Intel Transition, it was modified so that developers could easily create a universal binary to remain compatible with both the Intel-based and PowerPC-based Macintosh.

Compatibility

Software

To permit a smooth transition from Mac OS 9 to Mac OS X, the Carbon Application Programming Interface (API) was created. Applications written with Carbon can be executed natively on both systems. On the other hand, the APIs that Mac OS X inherited from Openstep are not backward compatible with earlier versions of Mac OS. These APIs are now referred by Apple as Cocoa. This heritage is highly visible for Cocoa developers, since most Cocoa class names begin with the "NS" prefix, for Nextstep.

Mac OS X used to support the Java Platform as a "preferred software package" — in practice this means that applications written in Java fit as neatly into the operating system as possible while still being cross-platform, and that graphical user interfaces 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."^[11]

Since Mac OS X is based on UNIX, most software packages written for BSD or Linux can be recompiled to run on it. Projects such as Fink, MacPorts and pkgsrc provide pre-compiled or pre-formatted packages. Since version 10.3, Mac OS X has included X11.app, Apple's version of the X Window System graphical interface for Unix applications, as an optional component during installation.^[12] Up to and including Mac OS X v10.4 (Tiger), Apple's implementation was based on the X11 Licensed XFree86 4.3 and X11R6.6. All bundled versions of X11 feature a window manager which is similar to the Mac OS X look-and-feel and has fairly good integration with Mac OS X, also using the native Quartz rendering system. Earlier versions of Mac OS X (in which X11 has not been bundled) can also run X11 applications using XDarwin.

Hardware

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 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.^[13] And, the newest version of OS X, Leopard has dropped support for PowerPC G3. However, tools such as XPostFacto and patches applied to the installation disc have been developed by third parties to enable installation of newer versions of Mac OS X on 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.

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. Classic is not supported on newer Intel-based Macs and was dropped in Mac OS X v10.5.

A few users experienced a surprise: Mac OS X was supported on Mac OS machines that came with a G3 or later processor from the factory — not machines with third-party processor cards. For example, a Power Mac 7300 whose CPU chip failed could be easily upgraded with a G3 processor on a "daughter card," which often cost nearly the same as an exact replacement of the original chip. The user could then go to the same store and buy the Mac OS X upgrade on CD-ROM. This is not guaranteed to work, however.

Apple Intel transition

In April 2002, eWeek reported a rumor that Apple had a version of Mac OS X code-named Marklar which ran on Intel x86 processors. 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.^[14] These rumors subsided until late in May 2005, when various media outlets, such as the Wall Street Journal^[15] and CNET^[16], 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, but will stop supporting it during the transition to Intel CPUs. Included in the new OS for the Intel-based Macs is Rosetta, a binary translation layer which 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 such as 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.^[17]

Software that is only available for PowerPC is supported with Rosetta. However, Apple encourages developers to produce universal binaries with support for both PowerPC and x86.^[18] 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, are not supported on Intel Macs. While Intel Macs will be able to run PowerPC, x86, and universal binaries, PowerPC Macs will only support universal and PowerPC builds.

Support for the PowerPC platform remains in OS X v10.5. Jobs also confirmed rumors that Apple has had versions of Mac OS X running on Intel processors for most of its developmental life. Such cross-platform capability already existed in Mac OS X's lineage, as said earlier; Openstep was ported to many architectures, including x86, and Darwin included support for both PowerPC and x86. 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 compatible with conventional x86 hardware has been developed by the OSx86 community and is available through file-sharing networks such as BitTorrent.

Prominent features

• Quartz's internal imaging model correlates well with the Portable Document Format (PDF) imaging model, making it easy to output PDF to multiple devices.
• Full-color, continuously scalable icons.
• Drop shadows around window and isolated text elements to provide a sense of depth.
• Global application Services menu – 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 dialog boxes 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.
• Dashboard (introduced in version 10.4) supports small applications called desktop widgets that can be called up and dismissed in one keystroke.
• Exposé (introduced in version 10.3) instantly displays all open windows as thumbnails for easy navigation to different tasks, displays all open windows as thumbnails from the current application, and hides 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 (256-bit keys on version 10.5).
• 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, with optional 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.
• Time Machine (introduced in 10.5) - backup technology that allows users to view and restore previous versions of files and application data.
• Spaces (introduced in 10.5) - program that can create and manage multiple virtual desktops and display them in an Exposé-like interface.
• Quick Look (introduced in 10.5) - allows dynamic previews of files (including videos and multi-page documents) without opening their parent applications.

Pricing

Mac OS X comes included in the price for new Macs. Minor updates are free and can be downloaded using Software Update. Major upgrade, server and academic prices are detailed below. 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 which include "testing and development only" licenses for both shipping and pre-release versions of Mac OS X.

The table represents the pricing of Mac OS X Leopard as of November 8 2007. The pricing was obtained from the relevant online Apple Store for the country.^[19] Prices are listed first in order of the five major reserve currencies, and then in alphabetical order. Pricing within the Eurozone is consistent, thus individual countries which use the Euro are not represented individually.

Versions

The character X is a Roman numeral and is officially pronounced "ten".^[20] It is the next release following the numbering of previous Macintosh operating systems such as Mac OS 8 and Mac OS 9.

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 marketed as "Panther", and 10.4 as "Tiger". "Leopard" is the name for the current release version 10.5. "Panther", "Tiger" and "Leopard" are registered as trademarks of Apple, but "Cheetah", "Puma" and "Jaguar" have never been registered. Apple has also registered "Lynx" and "Cougar" as trademarks.^[21]

Computer retailer Tiger Direct sued Apple for its use of the name "Tiger". But on May 16, 2005 a US federal court in the Southern District of Florida ruled that Apple's use does not infringe on Tiger Direct's trademark.^[22]

Timeline of Mac operating systems

Mac OS X 10.0 (Cheetah)

On March 24 2001, Apple released Mac OS X v10.0 (internally codenamed Cheetah).^[23] The initial version was slow, not feature complete, and had very few applications available at the time of its launch, mostly from independent developers. While many critics suggested that the operating system 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 some bug fixes, kernel panics became much less frequent.

Mac OS X 10.1 (Puma)

Later that year on September 25 2001, Mac OS X v10.1 (internally codenamed Puma) was released.^[24] It had better performance and provided 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 later re-released the CDs in an actual stripped-down format that didn't facilitate installation on such systems.

On January 7 2002, Apple announced that Mac OS X was to be the default operating system for all Macintosh products by the end of that month.^[25]

Mac OS X 10.2 (Jaguar)

On August 23 2002,^[26] Apple followed up with Mac OS X v10.2 "Jaguar", the first release to use its code name as part of the branding.^[27] It brought great performance enhancements, a sleeker look, and many powerful enhancements (over 150, according to Apple), including Quartz Extreme for compositing graphics directly on an ATI Radeon or NVIDIA GeForce2 MX AGP-based video card with at least 16 MB of VRAM, a system-wide repository for contact information in the new Address Book, and an instant messaging client named iChat.^[28]

The Happy Mac which had appeared during the Mac OS startup sequence for almost 18 years was replaced with a large grey Apple logo with the introduction of Mac OS X 10.2.

Mac OS X 10.3 (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. Panther included as many or more new features as Jaguar had the year before, including an updated Finder, incorporating a brushed-metal interface, Fast User Switching, Exposé (Window manager), FileVault, Safari, iChat AV which added video-conferencing features to iChat, improved Portable Document Format (PDF) rendering and much greater Microsoft Windows interoperability.^[29] But, support for some early G3 computers such as "beige" Power Macs and "WallStreet" PowerBooks was discontinued.

Mac OS X 10.4 (Tiger)

Mac OS X v10.4 "Tiger" was released on April 29 2005. Apple stated that Tiger contains more than 200 new features.^[30] As with Panther, certain older machines were no longer supported; Tiger requires a Mac with a built-in FireWire port.^[13] Among the new features, Tiger introduced Spotlight, Dashboard, Smart Folders, updated Mail program with Smart Mailboxes, QuickTime 7, Safari 2, Automator, VoiceOver, Core Image and Core Video.

Tiger's retail package was updated and reduced in size around the end of April 2006. It was called Mac OS X 10.4.3, and replaced the first release in retail stores.^[31]

On January 10, 2006, Apple released the first Intel-based Macs along with the 10.4.4 update to Tiger. This operating system functioned identically on the PowerPC-based Macs and the new Intel-based machines.^[32] Because the implementation of the OS is built separately for the two processors, in implementation the PowerPC version and Intel versions are two separate installers (one cannot use the PowerPC installer to install the OS onto an Intel-based Mac).

At some time in 2006 the retail packages were again updated with 10.4.6, also a PowerPC-only DVD installer. No retail package for an Intel-based Tiger Installer was released by Apple.

The latest update to Tiger has been 10.4.11(November 14,2007).

Mac OS X 10.5 (Leopard)

Mac OS X v10.5 "Leopard" was released on October 26, 2007. Leopard supports both PowerPC- and Intel x86-based Macintosh computers. The single DVD works for all supported Macs (including 64-bit machines). New features include an updated Finder, Time Machine, Spaces, Boot Camp pre-installed,^[33] full support for 64-bit applications (including graphical applications), new features in Mail and iChat, and a number of new security features.

Leopard is an Open Brand UNIX 03 registered product on the Intel platform. It is also the first BSD-based OS to receive the UNIX 03 certification.^[34][35]

The standard Mac OS Up-To-Date upgrade package is available to all customers who purchased a qualifying new Mac system from Apple or an Apple Authorized Reseller on or after October 1st, 2007, for a modest shipping and handling fee.^[36]

Languages

Mac OS X is available in the following languages: