Classic Mac OS

"Classic" Mac OS
MacOS original logo.svg
Mac OS 9.0.4 emulated inside of the SheepShaver emulator.png
Screenshot of Mac OS 9
DeveloperApple Computer, Inc.
OS familyMacintosh
Working stateHistoric, not supported
Source modelClosed source
Initial releaseJanuary 24, 1984; 34 years ago (1984-01-24)[1][2]
Latest release9.2.2 / December 5, 2001; 17 years ago (2001-12-05)[3]
Marketing targetPersonal computing
Kernel typeMonolithic for 68k, nanokernel for PowerPC
Default user interfaceGraphical
LicenseCommercial software, proprietary software
Succeeded bymacOS (previously named
"Mac OS X" and "OS X")
Support status
Unsupported as of February 1, 2002

Classic Mac OS is a colloquial term used to describe a series of operating systems developed for the Macintosh family of personal computers by Apple Inc. from 1984 until 2001, starting with System 1 and ending with Mac OS 9. The Macintosh operating system is credited with having popularized the graphical user interface concept.[4] It was included with every Macintosh that was sold during the era it was developed, and many updates to the system software were done in conjunction with the introduction of new Macintosh systems.

Apple released the original Macintosh on January 24, 1984. The first version of the system software, which had no official name, was partially based on the Lisa OS, previously released by Apple for the Lisa computer in 1983. As part of an agreement allowing Xerox to buy shares in Apple at a favorable price, it also used concepts from the Xerox PARC Alto computer, which former Apple CEO Steve Jobs and other Macintosh team members had previewed.[1] This operating system consisted of the Macintosh Toolbox ROM and the "System Folder", a set of files that were loaded from disk. The name Macintosh System Software came into use in 1987 with System 5. Apple rebranded the system as Mac OS in 1996, starting officially with version 7.6, due in part to its Macintosh clone program.[5] That program ended after the release of Mac OS 8 in 1997.[6] The last major release of the system was Mac OS 9 in 1999.[7]

Initial versions of the System Software run one application at a time. With the introduction of System 5, a cooperative multitasking extension called MultiFinder was added, which was later integrated into System 7 as part of the operating system along with support for virtual memory. By the mid-1990s, however, contemporary operating systems such as Windows NT, OS/2 and NeXTSTEP had all brought pre-emptive multitasking, protected memory, access controls, and multi-user capabilities to desktop computers, The Macintosh's limited memory management and susceptibility to conflicts among extensions that provide additional functionality such as networking or support for a particular device,[8] led to significant criticism of the operating system, and was a factor in Apple's declining market share at the time.

After two aborted attempts at creating a successor to Macintosh System Software called Taligent and Copland, and a four-year development effort spearheaded by Steve Jobs' return to Apple in 1997, Apple replaced Mac OS with a new operating system in 2001 named Mac OS X. It retained most of the user interface design elements of the classic Mac OS, and there was some overlap of application frameworks for compatibility, but the two operating systems otherwise have completely different origins and architectures.

The final updates to Mac OS 9 released in 2001 provided interoperability with Mac OS X. The name "Classic" that now signifies the historical Mac OS as a whole is a reference to the Classic Environment, a compatibility layer that helped ease the transition to Mac OS X.[9]

Initial concept

The Macintosh project started in late 1978 with Jef Raskin, who envisioned an easy-to-use, low-cost computer for the average consumer. In September 1979, Raskin began looking for an engineer who could put together a prototype. Bill Atkinson, a member of the Apple Lisa team, introduced Raskin to Burrell Smith, a service technician who had been hired earlier that year.

Apple's original concept for the Macintosh deliberately sought to minimize the user's conceptual awareness of the operating system. Many basic tasks that had required more operating system knowledge on other systems could then be accomplished by mouse gestures and graphic controls on a Macintosh. This would differentiate it from its contemporaries such as MS-DOS, which use a command-line interface consisting of tersely abbreviated textual commands.

In January 1981, Steve Jobs completely took over the Macintosh project. Jobs and a number of Apple engineers visited Xerox PARC in December 1979, three months after the Lisa and Macintosh projects had begun. After hearing about the pioneering GUI technology being developed at Xerox PARC from former Xerox employees like Raskin, Jobs negotiated a visit to see the Xerox Alto computer and Smalltalk development tools in exchange for Apple stock options.[10] The final Lisa and Macintosh operating systems use concepts from the Xerox Alto, but many elements of the graphical user interface were created by Apple including the menu bar, pull-down menus, and the concepts of drag and drop and direct manipulation.[11]

Unlike the IBM PC, which uses 8 kB of system ROM for power-on self-test (POST) and basic input/output system (BIOS), the Mac ROM is significantly larger (64 kB) and holds key OS code. Much of the original Mac ROM was coded by Andy Hertzfeld, a member of the original Macintosh team. He was able to conserve precious ROM space by writing routines in assembly language code optimized with "hacks," or clever programming tricks.[12] In addition to the ROM, he also coded the kernel, the Macintosh Toolbox, and some of the desktop accessories (DAs). The icons of the operating system, which represent folders and application software, were designed by Susan Kare, who later designed the icons for Microsoft Windows 3.0. Bruce Horn and Steve Capps wrote the Macintosh Finder, as well as a number of Macintosh system utilities.

Apple was very aggressive in advertising their new machine. After it was created, the company bought all 39 pages of advertisement space in the 1984 November/December edition of Newsweek magazine. Apple was so successful in its marketing for the Macintosh that it quickly outsold its more sophisticated predecessor, the Lisa. Apple quickly developed a product named MacWorks, which allowed the Lisa to emulate Macintosh system software through System 3, by which time it had been discontinued as the rebranded Macintosh XL. Many of Lisa's operating system advances would not appear in the Macintosh operating system until System 7 or later.

Other Languages
español: Mac OS Classic
한국어: 맥 OS의 역사
Bahasa Indonesia: Mac OS Klasik
lietuvių: Mac OS
日本語: Classic Mac OS
română: Classic Mac OS
русский: Mac OS
українська: Mac OS Classic