Mac OS 9

Mac OS 9 is the last version of what has become known as the classic Mac OS, introduced by Apple Computer on October 23, 1999.

Mac OS 9 was advertised by Apple as having "50 new features", including Sherlock 2, which was a definite improvement over the original Sherlock, sporting a QuickTime metallic appearance (which some people detested). Apple also was quick to point out OS 9's 128-bit encryption capabilities. Interestingly, when in the "About This Computer" window, which shows the amount of memory being used, command-clicking on the Mac OS 9 picture sends you to Apple's page about their OS. Another feature for laptops was the "Save Memory to Disk" option, found under the Energy Saver Control Panel. It was meant to perform the same function as "hibernate" on PC-compatible laptops. However, it was found to corrupt users' hard drives upon the first use. Apple quickly distributed a patch, in the form of a system extension. It did not fix the problem, but merely greyed out the option, so that it could not be selected.

Codenamed Sonata, and originally intended to debut as Mac OS 8.7, Mac OS 9 is, by some, considered the most functional and stable version of the original Mac OS, though OS 9 still does not have some features common to modern operating systems, such as protected memory (which, reportedly was implemented in beta versions of Mac OS 9.1, but pulled at Steve Jobs's command), and pre-emptive multitasking. However, it did ship from Apple with many improvements over earlier versions, such as improved OpenTransport networking, and an upgraded search tool (Sherlock 2), though it did retain the Platinum theme introduced in Mac OS 8. Unlike previous versions, it supports multiple users (University of Chicago, n.d.) without third-party additions. Perhaps most importantly, almost all of OS 9 was written in code which was compatible with PowerPC microprocessors. Earlier versions of the Mac OS depended heavily on emulation of the older Motorola 680x0 series of processors. While most of the code was now PPC-only (indeed, Mac OS 9 doesn't run on 680x0 CPUs), there are still many strings in the System suitcase which make references to obsolete 680x0 machinery.

Versions of Mac OS 9

 * Mac OS 9.0
 * Mac OS 9.0.2
 * Mac OS 9.0.3
 * Mac OS 9.0.4
 * Mac OS 9.1
 * Mac OS 9.2
 * Mac OS 9.2.1
 * Mac OS 9.2.2

Apple updated OS 9 with a series of bugfixes and minor enhancements, most notably versions 9.0.4 and 9.1, in 2000 and 2001. Another update, Mac OS 9.2, was introduced in 2002, but only to improve the functioning of the Classic environment in the new Mac OS X. However, OS 9.2 is a fully functional operating system and can be used on Macs that do not have an OS X-only boot.

The End of Mac OS 9
In May of 2002, at Apple's Worldwide Developers Conference in San Jose, California, Apple CEO Steve Jobs delivered a mock "funeral" for Mac OS 9 during his keynote address, dressed in black and toting a coffin. The purpose of the theatrics was to announce that Apple had stopped all development of OS 9. Mac OS 9.2.2 was the final version of Mac OS 9, and indeed, of the classic Mac OS.

Despite this, Mac OS 9 lives on as the operating system of choice on millions of existing Macintosh computers, and as of June of 2004, was even still being shipped as a stand-alone operating system (along with OS X) on the Power Macintosh G4, only available directly from Apple as a custom to order (CTO) model. (This model was eventually terminated in late 2004.) Mac OS 9's modernised successor, Mac OS X, still uses OS 9 to provide a compatibility layer called the Classic environment for applications and hardware that expect to be running under OS 9. Apple has provided Carbon, a toolkit for making applications that run natively under OS X and OS 9.

Sources and References

 * University of Chicago, Physical Sciences Division. (n.d.). Configuring Multiple Users in OS 9. Retrieved December 27, 2003 from http://psdds.uchicago.edu/docs/OS9MultiUser.html
 * University of Chicago, Physical Sciences Division. (n.d.). Configuring Multiple Users in OS 9. Retrieved December 27, 2003 from http://psdds.uchicago.edu/docs/OS9MultiUser.html