mac os x

Mac OS X is the latest version of the Mac OS operating system for Macintosh computers. The operating system was first commercially released in 2001. It consists of two main parts: Darwin, an open source Unix-like environment which is based on the BSD source tree and the Mach microkernel, adapted and further developed by Apple Computer with involvement from independent developers; and a proprietary GUI named Aqua, developed by Apple. 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. Some people read it as the letter X and pronounce it "ex". One reason for this interpretation is the tradition of giving Unix-like operating system names ending with the letter x (e.g. AIX, IRIX, Linux, Minix, Ultrix, Xenix). Another reason is Apple's tendency to refer to specific versions in print as (for example) "Mac OS X 10.4". Mac OS X Server was also released in 2001. Architecturally identical to the workstation (client) version, it is differentiated by the inclusion of workgroup management and administration software tools, which provide simplified access to key network services, such as a mail server, a Samba server, a directory server, and a domain name server. It also has a different licensing model.

History

Main article: Mac OS X history Despite its branding as simply "version 10" of the Mac OS, it has a history largely independent of the earlier Mac OS releases. It 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' NeXT company after he was forced from Apple in 1985. Meanwhile, Apple attempted to create a "next generation" operating system of their own (see Taligent and Copland), but with little success. Eventually, NeXT's OS—by then called OPENSTEP—was selected to form the basis for Apple's next OS, and the company purchased NeXT outright. Jobs was rehired, 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.

Description

Mac OS X is a radical departure from previous Macintosh operating systems. Although the most significant architectural changes were under the surface, the Aqua GUI was the most striking and visible new feature. The use of soft edges, translucent colors and pinstripes (see: iMac) brought more color and texture to the windows and controls on the Desktop than OS 9's "Platinum" appearance offered, raising a great deal of controversy among users. Many older Macintosh users decried the interface as "toy-like" and lacking in professional polish, while others hailed the new GUI as a revolutionary Apple innovation. The look was instantly recognizable and even before the first version of Mac OS X was released, third-party developers started producing skins for skinnable applications like Winamp that looked like the Aqua interface. Apple has threatened legal action against people who make or distribute software which provides an interface which they claim is derived from their copyrighted design. This combination of GUI and kernel has recently become the most popular-selling Unix environment to date by sheer number of systems shipped. (Note that Mac OS X is not officially a UNIX OS, as Apple has not sought The Open Group's branding, claiming that the cost of certification would make the OS prohibitively expensive. The Open Group has sued Apple over alleged violation of the UNIX trademark and has stated that the maximum fee required to certify OS X as a UNIX would be US$110,000 total.) Mac OS X retains compatibility with older Mac OS applications by providing an emulation environment called Classic, which allows users to run Mac OS 9.x within Mac OS X, so that most older applications run as they would under Mac OS 9.x. In addition, the Carbon APIs were created to permit legacy code to be quickly ported to run natively on both Mac OS X and Mac OS 9.x. The NeXTSTEP/OpenStep APIs are still available, but Apple now calls the technology Cocoa. You can see the NeXTSTEP heritage in the Cocoa APIs by the fact that class names mostly begin with "NS" (for NeXTSTEP). A fourth option for developers is to write applications in the Java platform, which OS X supports 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, while being written in Swing, look almost exactly like native Cocoa interfaces. Mac OS X can run many BSD or Linux software packages once compiled for the platform. Compiled binaries are normally distributed as Mac OS X Packages; but some may still require command-line configuration or compilation. Projects like Fink and DarwinPorts provide precompiled or preformatted packages for many standard packages. Version 10.3 was the first to include Apple X11, Apple's version of the X11 graphical interface for Unix applications, as an optional component during install. Apple's implementation is based on XFree86 4.3 and X11R6.6, with its own window manager which mimics the native look, closer integration with Mac OS X and extensions to use the native Quartz rendering system and accelerate OpenGL.

Notable features

Uses a subset of the Portable Document Format (PDF) as the basis of its imaging model (Quartz)
Full color, continuously scalable icons (up to 128x128 pixels)
Drop shadow around window and isolated text elements to provide a sense of depth
Global spell checking and other powerful tools thanks to NeXT style application services
Anti-aliasing of widgets, text, graphics and window elements
New interface elements including sheets (non-modal dialogs attached to specific windows) and drawers
Interweaving windows (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 is called Quartz Extreme, and was first featured in Mac OS X 10.2 Jaguar.
Expos (introduced in version 10.3, "Panther") quickly tiles open windows and reveals files on your desktop, first featured in Mac OS X 10.3 Panther.
Pervasive use of Unicode throughout the operating system
Straightforward architecture for localisation of applications and other code, fully separates language dependencies from the core code of a program

Versions

On March 24 2001, Apple released Mac OS X 10.0 (codenamed Cheetah). It was praised for its completeness and stability at such an early point in its development (it being a total departure from previous Apple releases). Despite this, it was criticized for being slow, leading many (including Steve Jobs) to consider it merely a very good "beta" release. Later that year on September 25 2001, Mac OS X 10.1 (codenamed Puma) was released, increasing the performance of the system as well as providing missing features, such as DVD playback. On August 24 2002, Apple followed up with Mac OS X 10.2 (codenamed Jaguar), which brought profound performance enhancements, a newer, sleeker look, and many powerful enhancements (over 150, according to Apple).

Increased support for Microsoft Windows networks
Quartz Extreme for compositing graphics directly on the video card
An adaptive spam mail filter, based on latent semantic indexing
A system-wide repository for contact information in the new Apple Address Book
Apple Rendezvous networking (Apple's implementation of Zeroconf)
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 - with some user recompilation - printing to serial printers.

Mac OS X 10.3 (codenamed Panther), was released on October 24, 2003, and in addition to providing much improved performance also incorporated the most extensive update to the user interface. The update included as many or more new features as Jaguar the year before. On the other hand, support for some older "beige era" G3 computers was discontinued.

Updated Finder, incorporating a brushed-metal interface and fast-searching
Expos: a new system to manipulate windows
Fast User Switching: allows a user to remain logged in while another user logs in
iChat AV video-conferencing software
Improved PDF rendering to allow for extremely fast 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

Mac OS X 10.4 (codenamed Tiger), is due to be released in the first half of 2005. Tiger is promised to contain another 200 or more features.

Spotlight: A tool to quickly find items containing key words on your computer, including the contents of files
Dashboard: Widgets for common tasks available on a desktop overlay just a click away
iChat: A new version supports H.264 video in conferencing and allows for multi-party audio and video chats
QuickTime 7: the new version includes H.264 support and a completely re-written interface
Safari 2: this new version of the system's default web browser includes the ability to view RSS feeds directly in the browser
Automator: automates repetitive tasks without programming
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
Re-written Unix filesystem utilities, such as cp and rsync, designed to preserve files' resource forks

The current version of Mac OS X is version 10.3.8 (released on February 9, 2005). See Mac OS X Release History for complete listing of Mac OS X releases from Public Beta to current version.

Codenames

The codenames of OS X versions are taken from large felines. Version 10.0 was codenamed Cheetah, 10.1 was codenamed Puma, 10.2 was codenamed Jaguar, and 10.3 was codenamed Panther. In January 2003, Apple registered the trademarks Lynx (not yet used), Cougar (not yet used), Leopard (not yet used), and Tiger (version 10.4, scheduled for release in the first half of 2005). Starting with Jaguar, Apple has been using these codenames officially in marketing. There is a running joke in the Macintosh community that the "next" version of Mac OS X will be named Ocelot.