| System | Year | Comments |
| System 6.0.x | ||
| System 6.0 | June 1988 | Introduced Multi-Finder, and stable color for the Mac II. |
| System 6.0.1 | September 19, 1988 | Released with the IIx. |
| System 6.0.2 | late 1988 | Bug-fix update Our Mac Plus came with this System. |
| System 6.0.3 | March 7, 1989 | Released with the SE and SE/30. The first stable version of System 6.0.x. |
| System 6.0.4 | September 20, 1989 | Released with the IIci and the Portable. |
| System 6.0.5 | March 19, 1990 | Released with the IIfx (the wicked fast 40 MHz 68030) |
| System 6.0.6 | 1990 | Released with the Classic, LC, and IIsi. Was so unstable that 6.0.7 was almost simultaneously released. |
| System 6.0.7 | October 15, 1990 | Bug-fix release |
| System 6.0.8 | 1991 | Released after System 7.0. |
| System 7.x | ||
| System 7.0 (Download Full OS) |
May 1991 | First major rewrite of the System. Added many new features that Mac users today consider essential, most notably the "Alias." |
| System 7.0.1 (Download Full OS) |
September 1991 | Bug-fix update Did not irradiate "The Disappearing Folder Bug," 7.1 did. |
| Download 7 Tune-up for 7.0 and 7.0.1 ONLY! | ||
| System 7.0.1p | March 1992 | Bug-fix from System 7.0.1 but specifically for the Performa line only. Had special features for the novice user. Apple didn't support the Performa OS releases on other Macs. |
| System 7.1 | August 1992 | Major upgrade from 7.0 Introduced the "Fonts" folder and System Enablers. Our Quadra 610 came with the retail version of this System. |
| System 7.1p | early 1993 | For Performas only again. Was released simultaneously with 7.1 Apple didn't support the Performa OS releases on other Macs. |
| System 7.1.1 (System 7 Pro) |
October 1993 | Introduced features that were previously available separatly, AppleScript, QuickTime, and PowerTalk. |
| System 7.1.2 | March 1994 | This System was the first release that supported PowerPC chips and was shipped on the first Power Macs. (It was very buggy) |
| System 7.1.3 (Download Updater) |
1994 | The Hardware System Update 3.0 Our Quadra had this OS on it for a while. |
| System 7.5 (Download Full OS) |
1995 | This System integrated all of the "special features," for novice users of the p systems. This System introduced Apple Guide, and the progress bar at startup. Was the only System to have the Welcome to Macintosh Logo, and a progress bar. Was the first OS to come on a CD-ROM, and was still available on floppys. |
| System 7.5.1 | March 1995 | This System introduced the "Mac OS Logo" at startup. Also known as (free) System 7.5 Update 1.0 |
| System 7.5.2 | August 1995 | Shipped with PCI Power Macs. A different version shipped with PowerBook 190, 5300, and Duo 2300s. |
| System 7.5.3 | January 1996 | My Power Mac 5400 came with this OS on its System CD. |
| System 7.5.3L | 1996 | Shipped on Mac Clones only. |
| System 7.5.3 System 7.5 Update 2.0 (Download Updater) |
Wednesday, May 1, 1996 |
When any of the above 7.5.x were updated with System 7.5 Update 2.0 This downloadable updater will update 7.5, 7.5.1, and 7.5.2 |
| System 7.5.3 Updated to Revision 2 (Download Updater) |
Friday, June 7, 1996 |
When System 7.5.3 Revision 2 updater was installed. This downloadable updater will only update a factory-installed System 7.5.3 |
| System 7.5.3 Revision 2 (Download Full OS) |
1996 | Sold Commercially, and shipped on new Macs. |
| System 7.5.3 Revision 2.1 |
1996 | Only for the Performa 6400/180 and 6400/200. (Last Performa made.) |
| System 7.5.3 Revision 2.2 |
1996 | Shipped with Power Mac 9500/200 and Performa 6360. |
| System 7.5.4 | September 1996 | This System Software was officially announced, but was pulled before its release because of some heavy-duty bugs. |
| System 7.5.5 (Download Updater) |
Wednesday, September 18, 1996 |
Finally combined all the 7.5.3 versions. If you have any version of 7.5.3, you should definitely update to 7.5.5 My Power Mac 5400 came with this System pre-installed. (It has run with every System since, up to OS 8.6) |
| Mac OS 7.6 | January 1997 | I updated my 5400 to this, immediately after I purchased it. The first system to be called Mac OS. This was to support the clones of that period, so that they would be running "The Mac OS". |
| Mac OS 7.6.1 (Download Updater) |
Monday, April 7, 1997 |
The last of the System 7.x family. |