Digiware Software Blog
Macintosh System 7.0
When System 7 was released, it added huge features which would stay with Mac OS until present day. System 7 featured an improved GUI (Graphical User Interface), QuickTime, Virtual Memory, QuickDraw 3D, and PFS (Personal File Sharing). System 6 had used AppleTalk, which was a primitive version of PFS. System 7 quickly caught on as the standard OS on all Mac computers until System 8 revolutionized the market again.
The Macintosh SE was te computer that was caught in the middle of System 6.0.5 and System 7.0.1
The Macintosh SE was released while System 6.0.5 was the standard, and wasn't discontinued until long after System 7's reign of popularity. Most SE owners bought System 7 disks to upgrade when it came out, but there are still some rare Mac SE with System 6.0.5 or System 6.0.8 still on the Hard Drive. However, the Macintosh SE SuperDrive was shipped with System 7 pre-installed on the Hard Drive. Owning an SE with two disk drives insteac of a Mac Hard Drive made it easy to switch Mac Operating Systems, so most Mac SE's with two disk drives ran System 7 at one point. Nowadays most people run their Macs on System 7 if it's compatible, since System 7 is considered to be the superior Mac System.
Above is a screenshot of a Macintosh computer running a version of System 7. This Operating System was featured on many color Macintosh's, which made it Graphical User Interface very attractive for its time. Below is a picture of a Macintosh SE with two FDDs (Floopy Disk Drives) instead of the more expensive SE with one FDD and a hard drive with either System 6.0.5, 6.0.8, or 7.0.1 pre-installed as the OS.
Wikipedia Article: http://en.wikipedia.org/wiki/System_7
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