Mac OS, also referred to as System Software in earlier versions of the operating system, is the operating system designed by Apple for use on their line of Macintosh personal computers.
It is worth noting that releases before 3.x are usually buggy and unstable, and should not be used on your vintage Macintosh computer if you want it to do anything useful.
Screenshots of this build were provided in the BYTE magazine in 1984. This version has a black default background and has the Arrange menu.
The first leaked version of the Macintosh operating system. This version was the base for the Tour disk that came with the original Macintosh, and a non-tour version exists but boots only on special development hardware.
- System icons are of a prototype Macintosh with a Twiggy drive.
- Folder icons are round.
- The about box scene is much more simpler, done in MacPaint by Susan Kare, and is in the code, NOT a resource.
- The Alternate disk (Unknown Disk) system is present
- Grim Reaper icon in resources (unused)
- Key Caps crashes the machine and sometimes corrupts the display memory.
- Alternate Disk system, although unusually unscrapped, goes to the RAM. Opening a application destroys this data.
- Scroll bars do not grey out when there is no scroll space.
- Doesn't work with many applications.
This is the first official version of the Macintosh operating system. It came with the Macintosh 128k when it first released. This version is already pre-installed on a 400k floppy, which it also booted from and ran with 128k of RAM. Still based on the updated kernel of 0.85, this version is still quite buggy. However, most of the bugs from 0.85 were fixed and it is technically done.
A update to 0.97, had slight changes but is otherwise the same. The most common version of pre-System 6 OS'es.
Not much is known about this odd version, but we do know that it exists.
System 1.1g kernel with 2 disks packed with developing / debugging software. This used to be a rare version of the Mac OS until it was released on BetaArchive.
Technically the same as System 1.1, yet has several bug fixes. Recommended for your 128k if you can't get ahold of System 3.x.
Mac OS 6
System 6 was a version of Mac OS, It was released on April 1988. The operating system of the Apple Macintosh computer, which was used in the late 1980s prior to the introduction of System 7. It is still widely considered to be the best system software version for the Macintoshes compatible with it. Cooperative multitasking made its Macintosh debut in March 1985 with a program called Switcher, which allowed the user to launch multiple applications and switch between them. However, many programs and features did not function correctly with Switcher, and it did not come with the operating system, so it had to be acquired from Apple separately. System 6 featured a much more seamless approach called MultiFinder. MultiFinder originally debuted with System 5 (System file 4.2 / Finder 6.0). Multitasking under System 6 was optional — startup could be set to Finder or MultiFinder. If MultiFinder was selected, the Finder and its functions continued to run when an application was launched. The MultiFinder environment allowed users to see past the windows of running applications to view Finder icons such as the Trash, or the windows of other applications running in the background.
Mac OS System 7
System 7 (Codenamed "Big Bang") was initially released in May 1991.
Versions 7.0 to 7.1.1 only worked on the 68k platform; 7.1.2 added support for PowerPC processors.
Mac OS 8
Released on July 26, 1997, had the codename "Tempo".
Initially, the early beta releases of the product which were circulated to developers and Apple internal audiences, were branded as Mac OS 7.7 (superseding the current release, Mac OS 7.6). Afterwards, the software was later renamed to Mac OS 8 before the final release.
The fist two releases of Mac OS 8 still could be run on Motorola 68k processors, however version 8.5 dropped support for the 68k platform, only supporting PowerPC based Macintoshes.
Mac OS 9
Released on October 23, 1999, codenamed "Sonata".
Apple discontinued development of Mac OS 9 in May 2002.
There are a few good 68k Macintosh emulators available today, which have been ported to various platforms and operating systems. Most of these emulators can run the full range of 68k Macintosh System Software
There is one PowerPC emulator, SheepShaver, which runs Mac OS System 7.1.2 through 9.0.4, and has been ported to various operating systems. The reason Mac OS 9.1 and up don't run in SheepShaver is that SheepShaver lacks a Memory Management Unit emulator, something that the last few Mac OS Releases needed.