Web site: (not active)
Origin: USA
Category: Desktop
Desktop environment: GUI
Architecture: Motorola 68000
Based on: System 5
Wikipedia: System 6
Media: Install
The last version | Released: 6.0.8L | 1992
System 6 – a version of the Mac OS operating system, released in April 1988 by Apple Computer. The System 6 successor is System 7.
System 6 was shipped on either five 800-kB or two 1.44-MB floppy disks. It runs on all Macintosh computers that ran System Software 5, which means all systems with the Motorola 68000, 68020, and 68030 processors, with the exception of the original Macintosh (128k and 512k) from 1984. The first model of the Macintosh Quadra from 1991 already uses a Motorola 68040 processor and is therefore not compatible with System 6.
Like System 1.0 from 1984, System 6 is largely written in 68k assembler and Pascal. This makes it feel significantly more powerful than its successor System 7, especially on older hardware, and at the same time requires relatively few resources: a minimal installation takes up only 460 kB of storage space on the hard disk (or floppy disk) and only 320 kB of main memory after the operating system has started. A standard installation (Easy Install) takes up 1.4 MB of storage space and 650 kB of main memory. System 6 runs excellently on Macs that have no hard disk, but only one or two floppy disk drives.
As with System Software 5, System 6 offers cooperative multitasking through the MultiFinder: if a program is started from the MultiFinder, it remains in memory and passes control to the started program. If the program is terminated or passes control back to the MultiFinder, the MultiFinder can continue in the state in which it gave up control. However, Finder and MultiFinder cannot be run at the same time. Switching between the two Finder variants requires a restart. However, on Macs with little memory, using the classic Finder offers the advantage of having more memory available for the program being run, since the Finder always closes and deletes itself from the memory when a program is started.
System 6 offers 24-bit memory access, but without virtual memory, and can access a total of 8 MB of RAM, 10 MB on the Macintosh LC and LC II. It supports hard drives as well as CD-ROM and Zip drives. The Hierarchical File System (HFS) can manage partitions up to 2 GB in size. With a suitable NuBus graphics card, System 6 supports screen resolutions of up to 1600×1200 in 24-bit color depth. In addition to modems, Ethernet is also supported with suitable hardware.
System 6.0.1 was released with the Macintosh IIx in September 1988.
Version 6.0.2 followed in late 1988.
System 6.0.3 was included with the Macintosh SE/30 and the Macintosh IIcx in January 1989.
The Macintosh IIci and the Macintosh Portable were shipped with System 6.0.4 in September 1989.
System 6.0.5 was released with the Macintosh IIfx in March 1990.
The Macintosh Classic, the Macintosh IIsi and the Macintosh LC were shipped with System 6.0.6, which, however, had stability problems and bugs.
It was therefore replaced shortly afterwards by System 6.0.7 in October 1990.
System 6.0.8 was made available in April 1991, after the release of System 7 (March 1991).
The last version of System 6 is version 6.0.8L released in February 1992.
